Zn₂SnO₄-Based Photoelectrodes for Organolead Halide Perovskite Solar Cells

Abstract

We report a new ternary Zn 2 SnO 4 (ZSO) electron-transporting electrode of a CH 3 NH 3 PbI 3 perovskite solar cell as an alternative to the conventional TiO 2 electrode. The ZSO-based perovskite solar cells have been prepared following a conventional procedure known as a sequential (or two-step) process with ZSO compact/mesoscopic layers instead of the conventional TiO 2 counterparts, and their solar cell properties have been investigated as a function of the thickness of either the ZSO compact layer or the ZSO mesoscopic layer. The presence of the ZSO compact layer has a negligible influence on the transmittance of the incident light regardless of its thickness, whereas the thickest compact layer blocks the back-electron transfer most efficiently. The open-circuit voltage and fill factor increase with the increasing thickness of the mesoscopic ZSO layer, whereas the short-circuit current density decreases with the increasing thickness except for the thinnest one (∼100 nm). As a result, the device with a 300 nmthick mesoscopic ZSO layer shows the highest conversion efficiency of 7%. In addition, time-resolved and frequency-resolved measurements reveal that the ZSO-based perovskite solar cell exhibits faster electron transport (∼10 times) and superior charge-collection capability compared to the TiO 2 -based counterpart with similar thickness and conversion efficiency.

N-type metal-oxide electron transport layer for mesoscopic perovskite solar cells

“…This is because, besides the faster electron transport BaSnO3 and SrTiO3 have a better contact with perovskite, which makes the crystals grow more unity and the scaffold have a better surface coverage, resulting in a high shunt resistance and improved performance compared with the conventional mesoporous TiO2 in the control device. Recently, Bera et al [26] also reported that the mesoporous ternary oxide Zn2SnO4 could significantly promote the crystallization of hybrid perovskite layers and serve as an efficient electron transporting material in perovskite solar cells, although the Zn2SnO4 was firstly used as ETL in MPSC by Oh et al [27]. Both of them noticed that the Zn2SnO4-based PSC exhibited much faster electron transport and superior charge collection capability than TiO2-based PSC under similar condition.…”

Improving the Performance of a Perovskite Solar Cell by Adjusting the Dispersant for Titanium Dioxide

“…In addition, the ETL can provide a larger interface contact site to load the perovskite pigments and afford faster charge extraction . To date, many ETL materials such as ZnO, Nb 2 O 5 , SnO 2 , CdS, ZnSnO 3 , SrTiO 3 , and WO 3 have been successfully applied to PSC devices. Among them, mesoporous TiO 2 is the most widely used.…”

“…[10][11][12][13][14] Thet ypical PSC device consists of an anode,e lectrontransport layer (ETL), perovskite absorption layer, holetransport layer (HTL), and cathode.T he ETL is used to collect and transport electronsi nt he process of converting solar energy into electricity.I naddition, the ETL can providea larger interface contacts ite to load the perovskite pigments and afford faster charge extraction. [15] To date,m any ETL materials such as ZnO, [16,17] Nb 2 O 5 , [18,19] SnO 2 , [20,21] CdS, [22,23] ZnSnO 3 , [24][25][26] SrTiO 3 , [27,28] and WO 3 [29] have been successfully applied to PSC devices.A mong them, mesoporousT iO 2 is the most widely used. However, ag reat deal of interfacetrap states are formed in the mesoporous TiO 2 layer during the processo ff abricating PSC devices, [30][31][32][33] and trap states have an egative effecto nc harge recombination and charget rans-port, which in turn influences the solar cell voltage and current.…”

Niobium Doping Effects on TiO2 Mesoscopic Electron Transport Layer‐Based Perovskite Solar Cells

“…There have been many studies to match appropriate hole-transport materials (HTMs) with LAMs in mesoscopic devices. [14,15] Those approaches were effective for adjusting electron transport and recombination properties and device stability. [7,8] Ah igh performance and less hysteresis in photovoltaicp roperties could be obtained by modifying the meso-porousE TM.…”

“…[8] Recently,m etal-oxide-based mesoporous ETMs have been studied with emphasis on modifications of morphology/structure, [9] chemical/physical properties of the ETM/ LAM interfaces, [10] the electronic band structure, [11][12][13] and the materiali tself. [14,15] Those approaches were effective for adjusting electron transport and recombination properties and device stability.…”