Semitransparent Perovskite Solar Cells for Photovoltaic Application

Abstract

Photovoltaic technology, which can directly convert solar radiation into electric power, is regarded as the most efficient way to utilize renewable solar energy. As an emerging photovoltaic technology, perovskite solar cells (PSCs) have shown a stunning increase in power conversion efficiency (PCE) from 3.8% [1] to 25.7% [2] over the past few years. This progress has relied on material properties, such as large optical absorption coefficient, [3,4] long carrier diffusion length [5,6] and high carrier mobility, [7,8] and other effective methods including interface engineering, [9,10] carrier management [11,12] and additive engineering. [13][14][15] As the PCE approaches the Shockley-Queisser (SQ) limit for a single-junction solar cell (33.7%), [16] it becomes more challenging to improve the performance of PSCs. So, new concepts have to be proposed for further improvement of PCE.The most common solar cells are opaque to sunlight due to the use of metal electrodes, and can only be used as independent photovaltics. Unlike opaque solar cells, ST solar cells hold the potential for some special applications combining light transmission and solar energy harvest. Among existing solar cells, PSCs are the most promising candidates for ST solar cells. Crystalline silicon solar cells have about 90% market share due to their high efficiency and low cost. However, they can not be semi-transparent (ST). GaAs solar cells with high record efficiency (29.1% [2] ) can be ST. [17] But the cost of ST-GaAs solar cells is much higher than ST-PSCs. Cu(In,Ga)Se 2 (CIGS) and CdTe solar cells with low cost and high efficiency (23.4% [2] for GIGS, 22.1% [2] for CdTe) can be ST. [18,19] However, element scarcity of CIGS and toxicity of CdTe make corresponding ST solar cells less competitive than ST-PSCs. The advantages of low cost and optimized photoactive layer thickness (100-200 nm) render organic solar cells suitable for ST solar cells, [20] though the efficiency of ST organic solar cells is not as high as ST-PSCs. As ideal ST solar cells, ST-PSCs have shown the successful application in integrating into urban scenarios, such as building-integrated photovoltaics (BIPVs) and solar-powered vehicle. [21,22] The other application advantage of ST-PSCs is the tandem photovaltic application.Since early in their development, ST-PSCs have usually been used as the top cell to prepare four-terminal tandem solar cells. In that case, a PSC with some kind of transparent conductive material as the electrode layer serves as the top cell, which can use the short wavelength light to generate electrons and holes, and leave the long wavelength light through the ST solar cell. Tandem solar cells combining a ST perovskite cell with a low bandgap bottom cell are ideal devices to reach ultrahigh efficiency beyond the SQ limit for single-junction solar cells. [23,24] Among several candidates for the bottom cell, silicon [25,26] (1.1 eV) and CIGS [27,28] (1.15 eV) are appropriate choices when considering the cost and efficiency of the resulting tandem cell. The...

Semitransparent Perovskite Solar Submodule for 4T Tandem Devices: Industrial Engineering Route Toward Stable Devices

“…All modules were performed with a design of 22 cells series connected: the voltage of the module is the sum of the voltage of all cells. Reference PSM with Au shows a PCE of 15.94%, fill factor (FF) of 71.13%, current (I) of 113.41 mA, and voltage (V) of 23.92 V. voltage and current of the PSM: this can be speculated by a series of factors, such as a better band alignment between this interface respect to Spiro-MeOTAD/MoO x , less damaging deposition process while operating with thermal evaporated Au and lower shunt resistance caused by the presence of less points of nonradiative recombination [36].…”

Pure-Phase, Large-Grained Wide-Band-Gap Perovskite Films for High-Efficiency, Four-Terminal Perovskite/Silicon Tandem Solar Cells

“…To achieve high-efficiency four-terminal perovskite/silicon tandem solar cells, the performance of top semitransparent PSCs should be well optimized, of which the preparation of pure-phase, large-grained wide-band-gap perovskite films is extremely crucial. − The perovskite films are expected to contain fewer grain boundaries, interstitials, vacancies, and dangling bonds, contributing to the weaker nonradiative recombination and hence the better PCEs of final semitransparent PSCs. A one-step spin-coating method is generally adopted to prepare the wide-band-gap perovskite films, since it can modify the composition of lead halide perovskite film precisely and enable a film with the expected band gap. ,− However, it is currently difficult to obtain one with satisfactory characteristics in terms of surface coverage, thickness, crystallinity, stability, etc.…”

CsPbIBr2‐Based Bifacial Semitransparent Solar Cells for All‐Day Applications

“…[9] Semitransparent polymer solar cells (ST-PSCs) are widely considered to be one of the most promising technologies to increase the power output density and meet the requirements of PSCs in the fields of smart PV windows, solar-powered vehicles, building-integrated photovoltaics (BIPVs), tandem PVs, etc. [10][11][12] The ST-PSCs are bifacial solar cells, which have the double-sided power generation effect, meaning that light could be incident from both the top and bottom of the ST-PSCs. [13] Thus, ST-PSCs could absorb more photons and produce more energy output.…”

“…[ 9 ] Semitransparent polymer solar cells (ST‐PSCs) are widely considered to be one of the most promising technologies to increase the power output density and meet the requirements of PSCs in the fields of smart PV windows, solar‐powered vehicles, building‐integrated photovoltaics (BIPVs), tandem PVs, etc. [ 10–12 ]…”