Surface Engineering of ZnO Thin Film for High Efficiency Planar Perovskite Solar Cells

Abstract

Sputtering made ZnO thin film was used as an electron-transport layer in a regular planar perovskite solar cell based on high quality CH3NH3PbI3 absorber prepared with a two-step spin-coating. An efficiency up to 15.9% under AM 1.5G irradiation is achieved for the cell based on ZnO film fabricated under Ar working gas. The atmosphere of the sputtering chamber can tune the surface electronic properties (band structure) of the resulting ZnO thin film and therefore the photovoltaic performance of the corresponding perovskite solar cell. Precise surface engineering of ZnO thin film was found to be one of the key steps to fabricate ZnO based regular planar perovskite solar cell with high power conversion efficiency. Sputtering method is proved to be one of the excellent techniques to prepare ZnO thin film with controllable properties.

Metal Oxides as Efficient Charge Transporters in Perovskite Solar Cells

“…[110] Furthermore, ZnO can be formed into a wide range of nanostructures, such as nanoparticles, nanowires, and nanorods. [112] It was observed that the sputtering atmosphere had a crucial effect on the surface properties of the ZnO and, consequently, on the performance of the PSCs. [112] It was observed that the sputtering atmosphere had a crucial effect on the surface properties of the ZnO and, consequently, on the performance of the PSCs.…”

“…[111] Recently, high-efficiency PSCs with a PCE of 15.9% have also been realized using sputtered ZnO as the ETM. [112] The primary concern when using ZnO as an ETM is its chemical instability, which is a result of its basic nature and the resultant deprotonation of the perovskite surface. [112] The primary concern when using ZnO as an ETM is its chemical instability, which is a result of its basic nature and the resultant deprotonation of the perovskite surface.…”

Cadmium-doped flexible perovskite solar cells with a low-cost and low-temperature-processed CdS electron transport layer

“…On the other hand, the stability of perovskite lm deposited above ZnO as ETL layer has been a challenging issue to address. 9,33 Meanwhile, the high cost of high-purity organic semiconductor electron transfer materials also make them unaffordable to large scale industrial photovoltaic application. 34 Very recently, Ke and Wang employed the SnO 2 and CeO x as ETL in PSCs via solution-processed with a PCE of 17.21%, 14.3%, respectively, 35,36 however, the processing temperature are near to $150 C, which will limit the application in exible substrates.…”

Role of Metal Oxide Electron‐Transport Layer Modification on the Stability of High Performing Perovskite Solar Cells

“…Other metal oxide thin films and their combinations with other metal oxides, such as ZnO, [63][64][65][66][67] Zn 2 SnO 4 , [68,69] WO 3 , [70,71] In 2 O 3 , [72] Nb 2 O 5 , [73] BaTiO 3 , [74] SrTiO 3 , [75] BaSnO 3 , [76] and ZrO 2 , [77] were also investigated forp otential use as the compact layer in PSCs. However,a mong these metal oxide compact layers, only ZnO is extensively investigated owing to its superior optoelectronic properties over TiO 2 .A lthough the high PCEs of PSCs based on c-ZnO showed tremendous potential, its instability remains the barrierf or furtheri mprovement.…”