Oxide–Metal–Oxide Based Transparent Electrodes and Their Potential Application in Semitransparent Perovskite Solar Cells‐Optical Modeling Studies

Abstract

Oxide–metal–oxide (OMO)‐based stacks are highly attractive by virtue of their favorable properties for being used as a top transparent electrode (TE) in semitransparent solar cells. Herein, getting the best trade‐off between performance and transparency is focused on by optimizing the OMO electrode and the device layers with the help of optical simulation. NiO/Ag/SnO2 as the OMO electrode integrated into a device having SnO2, Spiro‐OMeTAD, and MAPbI3 as the electron transport layer, hole transport layer, and photoactive layer, respectively, in n–i–p geometry is investigated. It is shown that an optimized OMO electrode in terms of average visible transparency (AVT) does not translate to the best device performance. It is found that for the overcoat to undercoat oxide layer ratio of 1.17, a maximum short‐circuit current density (JSC) of 4.34 mA cm−2 is achieved while a maximum AVT of 21.55% is obtained for a ratio of 0.78. On further optimization of the MAPbI3 thickness, for an oxide ratio of 1, a modeled device with 4.58 mA cm−2 with AVT of 31.55% is demonstrated. In addition, it is also found that by integrating an optical spacer layer after the OMO electrode, the JSC of the device shows a jump of >115% to 9.86 mA cm−2.

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

“…[14][15][16][17] Unfortunately, conventional transparent conductive oxides are generally difficult to be directly used as the top electrodes in ST-PSCs, because their deposition process requires sputtering or high-temperature process, which may greatly destroy the perovskite layer and hole transport layer (HTL). [18][19][20] In addition to introducing protective buffer layers or developing low-damage deposition techniques, [21] other emerging alternative top electrodes have also been developed to overcome this problem, such as metal nanowires electrodes, [22,23] graphene-based transparent electrodes, [24] dielectric/metal/ dielectric (DMD), [25] carbon nanotubes electrodes, [26,27] conductive polymer electrodes, [28] etc. Among them, DMD multilayer transparent electrodes not only show high conductivity and good transparency, but also could be deposited in a way that is nondamaging to the underlying active substances.…”

Figure-of-merit for assessment of semitransparent solar cells

“…An ST-SCs make use of different types of top transparent electrodes (TEs), such as carbon nanotubes, graphene layer, ultrathin metallic films, metallic nanowires, transparent conductive oxides, and dielectric-metal-dielectric (DMD) structures. [7][8][9][10][11][12][13][14][15][16][17][18][19] Apart from this, index-matching capping layers, such as lithium fluoride (LiF) and magnesium flouride (MgF 2 ), are also utilized for light management purposes to enhance the transparency and as well as efficiency by the selective transmission of wavelength through the device and by optical interference phenomenon within the stack, respectively. 20,21 It also has to be noted that the use of TEs at both ends also contributes toward the reduction of efficiency compared to a cell incorporating a thick metallic electrode due to the loss of reflected photons from the back electrode.…”

Light‐Wavelength‐Selective Transparent ITO/Ag/ITO/Ag/ITO Structure for Functional Energy Applications

“…[28,29] This technology has exhibited performance superior to single TCO films, leading to its use in various fields, including transparent solar cells, perovskites, and energy-saving glass. [28][29][30][31][32][33]…”