Modeling of 2D PV Devices/Single Atomically Sharp Lateral Monolayer p-n Heterojunction Solar Cells with Extraordinarily High Power Conversion Efficiency

Note[edit | edit source]

This is a literature review page to take optical and electrical parameters from existing 2D PV devices at the lab scale and scale them up to make a theoretical module. Then do simulation on them e.g. AOI, antireflection coating etc. in something like pvlib to provide system designers with the new module. It would be our pleasure if you share your experience in this area with us. (Discussion tab is top left of this page)

Single Atomically Sharp Lateral Monolayer p-n Heterojunction Solar Cells with Extraordinarily High Power Conversion Efficiency[1][1][1][edit | edit source]

Abstract: The recent development of 2D monolayer lateral semiconductor has created new paradigm to develop p-n heterojunctions. Albeit, the growth methods of these heterostructures typically result in alloy structures at the interface, limiting the development for high-efficiency photovoltaic (PV) devices. Here, the PV properties of sequentially grown alloy-free 2D monolayer WSe2-MoS2 lateral p-n heterojunction are explores. The PV devices show an extraordinary power conversion efficiency of 2.56% under AM 1.5G illumination. The large surface active area enables the full exposure of the depletion region, leading to excellent omnidirectional light harvesting characteristic with only 5% reduction of efficiency at incident angles up to 75°. Modeling studies demonstrate the PV devices comply with typical principles, increasing the feasibility for further development. Furthermore, the appropriate electrode-spacing design can lead to environment-independent PV properties. These robust PV properties deriving from the atomically sharp lateral p-n interface can help develop the next-generation photovoltaics.

• for electronic tuning (doping properties) dual gate tuning being used a lot, but this guys used single back gate tuning to increase active area

High efficiency graphene/MoS2/Si Schottky barrier solar cells using layer-controlled MoS2 films[2][2][2][edit | edit source]

Abstract: The isolation of two-dimensional (2D) materials and the possibility to assemblage as a vertical heterostructure have significantly promoted the development of ultrathin and flexible devices. Here, we demonstrate the fabrication of high efficiency graphene/MoS2/Si Schottky barrier solar cells with Molybdenum disulfide (MoS2) interlayers. MoS2 monolayers were prepared by sulfurizing pre-annealed molybdenum foil, which allows not only to precisely control the layer number, but also the nondestructive transference onto arbitrary substrates. The inserted MoS2 layers function as hole transport layer to facilitate the separation of electron-hole pairs as well as electron blocking layer to suppress the recombination at graphene/silicon interfaces. By optimizing the thickness of MoS2 layers, a high photovoltaic conversion efficiency of 15.8% was achieved in graphene/MoS2/Si solar cells. This study provides a novel approach for the synthesis of large-area MoS2 monolayers and their potential application for ultrathin and low-cost photovoltaic devices.

• they deposit pre-annealed Mo foil and the sulurize it
• MoS2 layer works as hole transport layer, so prevent e-h recombination at Si-Graphene interface
• By optimizing the thickness of MoS2 layers PCE 15.8% was achieved

Graphene and its derivatives for solar cells application[3][3][3][edit | edit source]

Abstract: Graphene has played the role of game-changer for conductive transparent devices indebted to its unique two dimensional (2D) structures and gained an exceptional opportunity to be employed in energy industry. In the past two decades graphene has been merged with the concept of photovoltaic (PV) material and exhibited a significant role as a transparent electrode, hole/electron transport material and interfacial buffer layer in solar cell devices. This review covers the different methods of graphene fabrication and broadly discusses the recent advances in graphene-based solar cells, including bulk heterojunction (BHJ) organic, dye-sensitized and perovskite solar cell deices. The power conversion efficiency surpassed 20.3% for graphene-based perovskite solar cells and hit the efficiency of 10% for BHJ organic solar cells. Except the part of charge extracting and transport to the electrodes, graphene has another unique role of device protection against environmental degradation via its packed 2D network structure and provides long-term environmental stability for PV devices. We highlighted a comparative study on the role of graphene and its derivatives in photovoltaic devices. After all, the potential issues and the perspective for future research in graphene-based materials for PV applications are presented.

• A good review paper
• Application of graphene-based materials for organic solar cells (OSCs)
• Graphene-based materials for dye-sensitized solar cells (DSSCs)
• Graphene-based materials for perovskite solar cells (PSCs)

Doping ZnO Electron Transport Layers with MoS2 Nanosheets Enhances the Efficiency of Polymer Solar Cells[4][4][4][edit | edit source]

Abstract: In this study, we incorporated molybdenum disulfide (MoS2) nanosheets into sol–gel processing of zinc oxide (ZnO) to form ZnO:MoS2 composites for use as electron transport layers (ETLs) in inverted polymer solar cells featuring a binary bulk heterojunction active layer. We could effectively tune the energy band of the ZnO:MoS2 composite film from 4.45 to 4.22 eV by varying the content of MoS2 up to 0.5 wt %, such that the composite was suitable for use in bulk heterojunction photovoltaic devices based on poly[bis(5-(2-ethylhexyl)thien-2-yl)benzodithiophene-alt-(4-(2-ethylhexyl)-3-fluorothienothiophene)-2-carboxylate-2,6-diyl] (PTB7-TH)/phenyl-C71-butryric acid methyl ester (PC71BM). In particular, the power conversion efficiency (PCE) of the PTB7-TH/PC71BM (1:1.5, w/w) device incorporating the ZnO:MoS2 (0.5 wt %) composite layer as the ETL was 10.1%, up from 8.8% for the corresponding device featuring ZnO alone as the ETL, a relative increase of 15%. Incorporating a small amount of MoS2 nanosheets into the ETL altered the morphology of the ETL and resulted in enhanced current densities, fill factors, and PCEs for the devices. We used ultraviolet photoelectron spectroscopy, synchrotron grazing incidence wide-/small-angle X-ray scattering, atomic force microscopy, and transmission electron microscopy to characterize the energy band structures, internal structures, surface roughness, and morphologies, respectively, of the ZnO:MoS2 composite films.

• In an OPV system, optimizing the active layer is key for obtaining a high power convention efficiency (PCE)
• by adding MoS2 sheets to ZnO active layer, they showed a PCE increase from 8.8% to 10.1%
• different concentrations tested, optimum is 0.5 wt%

Tunable black phosphorus heterojunction transistors for multifunctional optoelectronics[5][5][5][edit | edit source]

Abstract:

Symmetry-Controlled Reversible Photovoltaic Current Flow in Ultrathin All 2D Vertically Stacked Graphene/MoS2/WS2/Graphene Devices[6][6][6][edit | edit source]

Abstract: Atomically thin vertical heterostructures are promising candidates for optoelectronic applications, especially for flexible and transparent technologies. Here, we show how ultrathin all two-dimensional vertical-stacked type-II heterostructure devices can be assembled using only materials grown by chemical vapor deposition, with graphene (Gr) as top and bottom electrodes and MoS2/WS2 as the active semiconductor layers in the middle. Furthermore, we show that the stack symmetry, which dictates the type-II directionality, is the dominant factor in controlling the photocurrent direction upon light irradiation, whereas in homobilayers, photocurrent direction cannot be easily controlled because the tunnel barrier is determined by the doping levels of the graphene, which appears fixed for top and bottom graphene layers due to their dielectric environments. Therefore, the ability to direct photovoltaic current flow is demonstrated to be only possible using heterobilayers (HBs) and not homobilayers. We study the photovoltaic effects in more than 40 devices, which allows for statistical verification of performance and comparative behavior. The photovoltage in the graphene/transition-metal dichalcogenide-heterobilayer/graphene (Gr/ TMD-HB (MoS2/WS2)/Gr) increases up to 10 times that generated in the monolayer TMD devices under the same optical illumination power, due to efficient charge transfer between WS2 and MoS2 and extraction to graphene electrodes. By applying external gate voltages (Vg), the band alignment can be tuned, which in turn controls the photovoltaic effect in the vertical heterostructures. The tunneling-assisted interlayer charge recombination also plays a significant role in modulating the photovoltaic effect in the Gr/TMD-HB/Gr. These results provide important insights into how layer symmetry in verticalstacked graphene/TMD/graphene ultrathin optoelectronics can be used to control electron flow directions during photoexcitation and open up opportunities for tandem cell assembly.

We demonstrate that by stacking WS2/ MoS2 in between graphene electrodes, photovoltaic effects are extracted from TMDs, which otherwise would not exist in their isolated states even through contact engineering with graphene electrodes.

• Manually stacking WS2(1L) and MoS2(1L) shows no obvious photovoltaic effects individually, whereas sandwiching them together between graphene electrodes to form GrB/ WS2(1L)/MoS2(1L)/GrT, yields Isc and |Voc| reaching 140 nA and 2.7 mV.
• photocurrent direction could be reversed by switching the stacking sequences of WS2 and MoS2

2D Photovoltaic Devices: Progress and Prospects[7][7][7][edit | edit source]

Abstract: The discovery of the new class of 2D materials has stimulated extensive research interest for fundamental studies and applied technologies. Owing to their unique electronic and optical properties, which differ from their bulk counterparts and conventional optoelectronic materials, 2D materials at the atomic scale are very attractive for future photovoltaic devices. Over the past years, their great potential for photovoltaic applications has been widely investigated by creating a variety of specific device structures. Here, the recent progress made toward the exploitation of 2D materials for high-performance photovoltaic applications is reviewed. By addressing both lateral and vertical configurations, the prospects offered by 2D materials for future generations of photovoltaic devices are elucidated. In addition, the challenges facing this rapidly progressing research field are discussed, and routes to commercially viable 2D-material-based photovoltaic devices are proposed.

• is a good review paper on 2D PV
• In the following sections, we divide the realization of photovoltaic devices into two different configurations, i.e., lateral and vertical structures.
• Table I in page 13 summarize all parameters of 2D PV in Lit

Symmetry-Controlled Reversible Photovoltaic Current Flow in Ultrathin All 2D Vertically Stacked Graphene/MoS2/WS2/Graphene Devices[8][8][8][edit | edit source]

Abstract: Atomically thin vertical heterostructures are promising candidates for optoelectronic applications, especially for flexible and transparent technologies. Here, we show how ultrathin all two-dimensional vertical-stacked type-II heterostructure devices can be assembled using only materials grown by chemical vapor deposition, with graphene (Gr) as top and bottom electrodes and MoS2/WS2 as the active semiconductor layers in the middle. Furthermore, we show that the stack symmetry, which dictates the type-II directionality, is the dominant factor in controlling the photocurrent direction upon light irradiation, whereas in homobilayers, photocurrent direction cannot be easily controlled because the tunnel barrier is determined by the doping levels of the graphene, which appears fixed for top and bottom graphene layers due to their dielectric environments. Therefore, the ability to direct photovoltaic current flow is demonstrated to be only possible using heterobilayers (HBs) and not homobilayers. We study the photovoltaic effects in more than 40 devices, which allows for statistical verification of performance and comparative behavior. The photovoltage in the graphene/transition-metal dichalcogenide-heterobilayer/graphene (Gr/ TMD-HB (MoS2/WS2)/Gr) increases up to 10 times that generated in the monolayer TMD devices under the same optical illumination power, due to efficient charge transfer between WS2 and MoS2 and extraction to graphene electrodes. By applying external gate voltages (Vg), the band alignment can be tuned, which in turn controls the photovoltaic effect in the vertical heterostructures. The tunneling-assisted interlayer charge recombination also plays a significant role in modulating the photovoltaic effect in the Gr/TMD-HB/Gr. These results provide important insights into how layer symmetry in verticalstacked graphene/TMD/graphene ultrathin optoelectronics can be used to control electron flow directions during photoexcitation and open up opportunities for tandem cell assembly.

We demonstrate that by stacking WS2/ MoS2 in between graphene electrodes, photovoltaic effects are extracted from TMDs, which otherwise would not exist in their isolated states even through contact engineering with graphene electrodes.

• Manually stacking WS2(1L) and MoS2(1L) shows no obvious photovoltaic effects individually, whereas sandwiching them together between graphene electrodes to form GrB/ WS2(1L)/MoS2(1L)/GrT, yields Isc and |Voc| reaching 140 nA and 2.7 mV.
• photocurrent direction could be reversed by switching the stacking sequences of WS2 and MoS2

Towards efficient photon management in nanostructured solar cells: Role of 2D layered transition metal dichalcogenide semiconductors[9][9][9][edit | edit source]

Abstract: Photovoltaic devices are the source for future energy where the naturally abundant solar energy is converted into electricity using photoactive materials. An efficient photon management mechanism is essential for achieving high efficiency next generation solar cells. The use semiconducting two dimensional (2D) transition metal dichalcogenide (TMDCs) nanosheets light absorbing layer in modern solar cell is inevitable. Diverse large area synthesis tools to tailor nanosheets and its incorporation in solar cell cover the entire solar spectrum for enhanced photon management. In this review, the case to case use of TMDCs in various photovoltaic devices as an efficient absorber layer has been discussed. Experimental measures to overcome the limitations of pristine TMDC layers due to its atomic layer thickness were also reviewed. It can be seen that, the device performance of the TMDCs based solar cells is showing significant improvement in comparison with conversional silicon based photovoltaics

• This is a Review paper with focus on TMDs
• application in OPVs One of the most emerging fields in the photovoltaics is the organic photovoltaics (OPVs) due to flexibility, low cost, light weight and relative ease to fabricate large area. In OPVs, electron transport layer (ETL) or hole transport layer (HTL) which is placed in between the active layer and the cathode is inevitable to obtain high power convention efficiency (PCE). The role of this transport layer is to modify the work function of cathode and reduce the carrier recombination in the active layer. The exciting electronic and optical properties of layered TMDC semiconductors are now being placed as transport (e/h) layers in OPVs.

Two-dimensional materials in perovskite solar cells[10][10][10][edit | edit source]

Abstract: Organic-inorganic hybrid perovskite solar cells (PSCs) have experienced a rapid development in the pastfew years, reaching a certified efficiency over 23%. The semiconducting perovskite materials have showngreat potential for photovoltaic applications because of their outstanding optoelectronic properties.Meanwhile, two-dimensional (2D) materials have attracted increasing attention due to their exceptionalchemical, electrical and physical properties. Recently, the synergic effects due to the combination of 2Dmaterials and organic-inorganic hybrid perovskite materials have been revealed by many groups. In thisreview, recent works on the applications of 2D materials in PSCs are comprehensively presented anddiscussed. The progress and advantages of 2D materials as electrodes, charge transport layers and ad-ditives in PSCs are systemically reviewed. Finally, critical challenges and prospects of this researchfieldare addressed.

Flexible Solar Cells[edit | edit source]

Transparent Conductive Oxide-Free Graphene-Based Perovskite Solar Cells with over 17% Effi ciency[11][11][11][edit | edit source]

Abstract: Highly efficient transparent conductive oxide (TCO)‐free perovskite (CH3NH3PbI3) solar cells are demonstrated by using a graphene transparent anode and organic carrier transport materials. By adding a few nanometer‐thick MoO3 layer, wettability and work function of the graphene electrode are enhanced to enable a 17.1% power conversion efficiency, which is so far the highest efficiency for TCO‐free solar cells.

Superflexible, high-efficiency perovskite solar cells utilizing graphene electrodes: towards future foldable power sources[12][12][12][edit | edit source]

Abstract: With rapid and brilliant progress in performance over recent years, perovskite solar cells have drawn increasing attention for portable power source applications. Their advantageous features such as high efficiency, low cost, light weight and flexibility should be maximized if a robust and reliable flexible transparent electrode is offered. Here we demonstrate highly efficient and reliable super flexible perovskite solar cells using graphene as a transparent electrode. The device performance reaches 16.8% with no hysteresis comparable to that of the counterpart fabricated on a flexible indium-tin-oxide electrode showing a maximum efficiency of 17.3%. The flexible devices also demonstrate superb stability against bending deformation, maintaining >90% of its original efficiency after 1000 bending cycles and 85% even after 5000 bending cycles with a bending radius of 2 mm. This overwhelming bending stability highlights that perovskite photovoltaics with graphene electrodes can pave the way for rollable and foldable photovoltaic applications.

Visibly-Transparent Organic Solar Cells on Flexible Substrates with All-Graphene Electrodes[13][13][13][edit | edit source]

Abstract: Portable electronic devices have become increasingly widespread. Because these devices cannot always be tethered to a central grid, powering them will require low-cost energy harvesting technologies. As a response to this anticipated demand, this study demonstrates transparent organic solar cells fabricated on fl exible substrates, including plastic and paper, using graphene as both the anode and cathode. Optical transmittance of up to 69% at 550 nm is achieved by combining the highly transparent graphene electrodes with organic polymers that primarily absorb in the near-IR and near-UV regimes. To address the challenge of transferring graphene onto organic layers as the top electrode, this study develops a room temperature dry-transfer technique using ethylene-vinyl-acetate as an adhesion-promoting interlayer. The power conversion effi ciency achieved for fl exible devices with graphene anode and cathode devices is 2.8%–3.8% at for optical transmittance of 54%–61% across the visible regime. These results demonstrate the versatility of graphene in optoelectronic applications and it is important step toward developing a practical power source for distributed wireless electrical systems.

Ultrathin and flexible perovskite solar cells with graphene transparent electrodes[14][14][14][edit | edit source]

Abstract:

Flexible and light weight perovskite solar cells have attracted much attention recently for their broad potential applications especially in wearable electronics. However, highly flexible devices cannot be realized with the conventional transparent electrodes based on conductive oxides since they are rigid and brittle. Here, we demonstrate the fabrication of ultrathin and flexible perovskite solar cells with graphene transparent electrodes for the first time. The flexible devices with the structure of polyethylene terephthalate/graphene/poly(3-hexylthiophene)/CH3NH3PbI3/PC71BM/Ag are prepared on 20 mm-thick polyethylene terephthalate substrates by low-temperature solution process, which show the power conversion efficiency of 11.5% and high bending durability. Moreover, the devices demonstrate the power output per weight (specific weight) of about 5 W/g, which is much higher than those of conventional inorganic solar cells. This work paves a way for preparing flexible perovskite solar cells as well as other optoelectronic devices by using graphene transparent electrodes.

The Role of Graphene and Other 2D Materials in Solar Photovoltaics[15][15][15][edit | edit source]

Abstract: 2D materials have attracted considerable attention due to their exciting optical and electronic properties, and demonstrate immense potential for next-generation solar cells and other optoelectronic devices. With the scaling trends in photovoltaics moving toward thinner active materials, the atomically thin bodies and high flexibility of 2D materials make them the obvious choice for integration with future-generation photovoltaic technology. Not only can graphene, with its high transparency and conductivity, be used as the electrodes in solar cells, but also its ambipolar electrical transport enables it to serve as both the anode and the cathode. 2D materials beyond graphene, such as transition-metal dichalcogenides, are direct-bandgap semiconductors at the monolayer level, and they can be used as the active layer in ultrathin flexible solar cells. However, since no 2D material has been featured in the roadmap of standard photovoltaic technologies, a proper synergy is still lacking between the recently growing 2D community and the conventional solar community. A comprehensive review on the current state-of-the-art of 2D-materials-based solar photovoltaics is presented here so that the recent advances of 2D materials for solar cells can be employed for formulating the future roadmap of various photovoltaic technologies.

• Provskite shown > 20% PCE but poor stability prevents commercialization (page 3 of 35)

Highly flexible, high-performance perovskite solar cells with adhesion promoted AuCl3-doped graphene electrodes[16][16][16][edit | edit source]

Abstract: Super flexible TCO-free FAPbI3−xBrx planar type inverted perovskite solar cells with a 17.9% power conversion efficiency under 1 sun conditions were demonstrated by introducing an APTES (3-aminopropyl triethoxysilane) adhesion promoter between a PET flexible substrate and a AuCl3-doped single-layer graphene transparent electrode (TCE). Due to the formation of covalent bonds by the APTES inter-layer, the AuCl3-GR/APTES/PET substrate had excellent flexibility, whereas the AuCl3-GR/PET substrate and the ITO/PET substrate had significant degradation of the sheet resistance after a bending test due to the break-off or delamination of AuCl3-GR from the PET substrate and the cracking of ITO. Accordingly, the perovskite solar cells constructed on the AuCl3-GR/APTES/PET TCE substrate exhibited excellent bending stability and they maintained their PCE at over 90% of the initial value after 100 bending cycles at R ≥ 4 mm

Super-flexible bis(trifluoromethanesulfonyl)-amide doped graphene transparent conductive electrodes for photo-stable perovskite solar cells[17][17][17][edit | edit source]

Abstract: Super-flexible bis(trifluoromethanesulfonyl)-amide (TFSA)-doped graphene transparent conducting electrode (GR TCE)-based FAPbI3 − xBrx perovskite solar cells with 18.9% power conversion efficiency (PCE) for a rigid device and 18.3% for a flexible one are demonstrated because the TFSA-doped GR TCE reveals high conductivity and high transmittance. The unencapsulated TFSA-doped GR TCE-based cell maintained ∼95% of its initial PCE under a continuous light soaking of 1 Sun at 60 °C/30% relative humidity for 1000 h. In addition, the TFSA-doped GR TCE-based flexible perovskite solar cells show excellent bending stabilities, maintaining PCEs of ∼85, ∼75, and ∼35% of their original values after 5000 bending cycles, at R = 12, 8, and 4 mm, respectively

Graphene[edit | edit source]

Roll-to-roll production of 30-inch graphene films for transparent electrodes[18][18][18][edit | edit source]

Abstract; The outstanding electrical1, mechanical2,3 and chemical4,5 properties of graphene make it attractive for applications in flexible electronics6,7,8. However, efforts to make transparent conducting films from graphene have been hampered by the lack of efficient methods for the synthesis, transfer and doping of graphene at the scale and quality required for applications. Here, we report the roll-to-roll production and wet-chemical doping of predominantly monolayer 30-inch graphene films grown by chemical vapour deposition onto flexible copper substrates. The films have sheet resistances as low as ∼125 Ω □−1 with 97.4% optical transmittance, and exhibit the half-integer quantum Hall effect, indicating their high quality. We further use layer-by-layer stacking to fabricate a doped four-layer film and measure its sheet resistance at values as low as ∼30 Ω □−1 at ∼90% transparency, which is superior to commercial transparent electrodes such as indium tin oxides. Graphene electrodes were incorporated into a fully functional touch-screen panel device capable of withstanding high strain.

Are There Fundamental Limitations on the Sheet Resistance and Transmittance of Thin Graphene Films?[19][19][19][edit | edit source]

Abstract From published transmittance and sheet resistance data, we have calculated a figure of merit for transparent, conducting graphene films; the DC to optical conductivity ratio, σDC/σOp. For most reported results, this conductivity ratio clusters around the values σDC/σOp = 0.7, 4.5, and 11. We show that these represent fundamental limiting values for networks of graphene flakes, undoped graphene stacks, and graphite films, respectively. The limiting value for graphene flake networks is much too low for transparent-electrode applications. For graphite, a conductivity ratio of 11 gives Rs = 377Ω/◻ for T = 90%, far short of the 10 Ω/◻ minimum requirement for transparent conductors in current driven applications. However, we suggest that substrate-induced doping can potentially increase the 2-dimensional DC conductivity enough to make graphene a viable transparent conductor. We show that four randomly stacked graphene layers can display T ≈ 90% and 10 Ω/◻ if the product of carrier density and mobility reaches nμ = 1.3 × 1017 V−1 s−1. Given achieved doping values and attainable mobilities, this is just possible, resulting in potential values of σDC/σOp of up to 330. This is high enough for any transparent conductor application.

Electrode Grids for ITO-free Organic Photovoltaic Devices[20][20][20][edit | edit source]

Abstract; Silver grids are utilized to exclude the expensive use of indium tin oxide (ITO) in conjugated polymer photovoltaic devices. The grids are generated by electroless deposition from elastomeric microfluidic channels onto transparent substrates. The organic photovoltaic devices demonstrated here, with minimized series resistance, are confirmed to have characteristics comparable to devices exploiting ITO

Bending Fatigue Study of Sputtered ITO on Flexible Substrate[21][21][21][edit | edit source]

Abstract; Recently, there has been a tremendous rise in production of portable electronic devices. To produce flexible devices, flexible substrates should replace conventional glass substrates. Indium-tin-oxide (ITO) is the preferred transparent conducting layer used in the display technology. Although ITO has excellent sheet resistance and very good optical properties, ITO can crack at very low tensile strains which might cause failure in the conductive layer because of the unusual structure of a very thin film of brittle ceramic material applied to a polymer substrate. Therefore, the mechanics of ITO on flexible substrates has been thoroughly considered in the design and manufacturing of flexible devices. In a typical roll-to-roll manufacturing process, many challenges exist during the travel of the coated web over the rollers which produce bending stresses that might cause failure even if the stresses are below the yield strength of the material. Therefore, the high cycle bending fatigue of ITO thin films on flexible substrates is of a significant importance. In this work, high cycle bending fatigue experiments were conducted on ITO coated PET substrate. The effect of bending diameter, bending frequency, and sample width on the change in electrical resistance was investigated. High magnification images were obtained to observe crack initiation and propagating in the ITO layer. The goal of this work is to establish a baseline for a comprehensive reliability study of ITO thin films on flexible substrate. It was found that bending diameters as well as the number of bending cycles have a great influence on the electrical conductivity of the ITO layer.

Scale up perovskite solar cells (PSCs)[edit | edit source]

Upscaling of Perovskite Solar Cells: Fully Ambient Roll Processing of Flexible Perovskite Solar Cells with Printed Back Electrodes[22][22][22][edit | edit source]

Abstract: A scaling effort on perovskite solar cells is presented where the device manufacture is progressed onto flexible substrates using scalable techniques such as slot‐die roll coating under ambient conditions. The printing of the back electrode using both carbon and silver is essential to the scaling effort. Both normal and inverted device geometries are explored and it is found that the formation of the correct morphology for the perovskite layer depends heavily on the surface upon which it is coated and this has significant implications for manufacture. The time it takes to form the desired layer morphology falls in the range of 5–45 min depending on the perovskite precursor, where the former timescale is compatible with mass production and the latter is best suited for laboratory work. A significant loss in solar cell performance of around 50% is found when progressing to using a fully scalable fabrication process, which is comparable to what is observed for other printable solar cell technologies such as polymer solar cells. The power conversion efficiency (PCE) for devices processed using spin coating on indium tin oxide (ITO)‐glass with evaporated back electrode yields a PCE of 9.4%. The same device type and active area realized using slot‐die coating on flexible ITO‐polyethyleneterphthalate (PET) with a printed back electrode gives a PCE of 4.9%.

• Introducing other methods mostly used instead of spin coating

Perovskite SolarCells: Fromthe Laboratorytothe Assembly Line[23][23][23][edit | edit source]

Abstract: Despite the fact that perovskite solar cells (PSCs) have a strong potential as a next‐generation photovoltaic technology due to continuous efficiency improvements and the tunable properties, some important obstacles remain before industrialization is feasible. For example, the selection of low‐cost or easy‐to‐prepare materials is essential for back‐contacts and hole‐transporting layers. Likewise, the choice of conductive substrates, the identification of large‐scale manufacturing techniques as well as the development of appropriate aging protocols are key objectives currently under investigation by the international scientific community. This Review analyses the above aspects and highlights the critical points that currently limit the industrial production of PSCs and what strategies are emerging to make these solar cells the leaders in the photovoltaic field.

• a good review paper on scale up perovskite solar cells

Toward Industrial-Scale Production of Perovskite Solar Cells: Screen Printing, Slot-Die Coating, and Emerging Techniques[24][24][24][edit | edit source]

Abstract: Perovskite solar cells (PSCs) have attracted intensive attention of the researchers and industry due to their high efficiency, low material cost, and simple solution-based fabrication process. Along with the development of device configurations, materials, and fabrication techniques, the efficiency has rapidly increased from the initial 3.8 to recent 22.7%. However, fundamental studies on PSCs are usually yielded through lab-scale procedures and carried out on small-area (≤1 cm2) devices. Recently, various deposition methods, such as screen printing, slot-die coating, soft-cover coating, spraying coating, etc., have been developed to enlarge the device area from the millimeters to hundreds of centimeters scale. Herein, we discuss the advances of up-scaling of PSCs and outline the fabrication methods from lab-scale to industrial-scale. Screen printing and slot-die coating have been regarded as the most promising methods toward the mass production of PSCs, and more emerging techniques are also anticipated in this enterprise.

Outlook and Challenges of Perovskite Solar Cells toward Terawatt-Scale Photovoltaic Module Technology[25][25][25][edit | edit source]

Abstract: Perovskite solar cells based on organic-inorganic hybrid perovskites have emerged as a low-cost and high-efficiency thin-film photovoltaic (PV) technology that holds the potential to compete in the PV market. Developing scalable processes with solution deposition (e.g., blade, slot die, and spray coating) enables continuous roll-to-roll or sheet-to-sheet processing with flexible or rigid substrates that can be used for future terawatt-scale production of perovskite solar modules. Scaling up from laboratory-scale device fabrication based on spin coating to scalable deposition suitable for an industry setting generally requires re-evaluation/re-design of many factors associated with device fabrication and characterization. Here, we provide our perspective regarding large-scale manufacturing and deployment of perovskite PV technology. We discuss challenges in three key areas: (1) a scalable process for large-area perovskite module fabrication; (2) less hazardous chemical routes for perovskite solar cell fabrication; and (3) suitable perovskite module designs for different applications. Advances along these key areas are crucial to the success of perovskite PV technology in the future

• I received the article full text through ILLiad MTU library

Applications of Flexible PVs[edit | edit source]

A PCBM-assisted perovskite growth process to fabricate high efficiency semitransparent solar cells[26][26][26][edit | edit source]

Abstract: Developing highly efficient perovskite solar cells in a simple and rapid fashion will open the window for their potential commercialization. Semi-transparent devices are of great interest due to their attractive application in building integrated photovoltaics (BIPVs). In this study, efficient perovskite solar cells with good transparency in the visible wavelength range have been developed by a facile and low-temperature PCBM-assisted perovskite growth method. This method results in the formation of a perovskite-PCBM hybrid material at the grain boundaries which is observed by EELS mapping and confirmed by steady-state photoluminescence (PL) spectroscopy, transient photocurrent (TP) measurements and X-ray photoelectron spectroscopy (XPS). The PCBM-assisted perovskite growth method involves fewer steps and therefore is less expensive and time consuming than other similar methods. The semitransparent solar cells developed using this method exhibited power conversion efficiency (PCE) ranging from 12% to 4% depending on the average visible transmittance (AVT) ranging from 3% to 35%. The as-fabricated semitransparent perovskite solar cell with an active layer thickness of only about 150 nm, which is only less than half the active layer thickness of a typical perovskite solar cell, provided a PCE as high as 9.1% with an AVT of 18% and more than 12% with an AVT of 3%.

System Analysis[edit | edit source]

Cost-Performance Analysis of Perovskite Solar Modules[27][27][27][edit | edit source]

Abstract: Perovskite solar cells (PSCs) are promising candidates for the next genera-tion of solar cells because they are easy to fabricate and have high power conversion efficiencies. However, there has been no detailed analysis of the cost of PSC modules. We selected two representative examples of PSCs and performed a cost analysis of their productions: one was a moderate-efficiency module produced from cheap materials, and the other was a high-efficiency module produced from expensive materials. The costs of both modules were found to be lower than those of other photovoltaic technologies. We used the calculated module costs to estimate the levelized cost of electricity (LCOE) of PSCs. The LCOE was calculated to be 3.5–4.9 US cents/kWh with an efficiency and lifetime of greater than 12% and 15 years respectively, below the cost of traditional energy sources

An Analysis of the Cost and Performance of Photovoltaic Systems as a Function of Module Area[28][28][28][edit | edit source]

• this is a detailed analysis by NREL can be a good reference for some parameters assumptions

Building-Integrated Photovoltaics (BIPV) in the Residential Sector: An Analysis of Installed Rooftop System Prices[29][29][29][edit | edit source]

• this NREL analysis is good for rooftop case

References[edit | edit source]