Observing and Understanding the Corrosion of Silver Nanowire Electrode by Precursor Reagents and MAPbI₃ Film in Different Environmental Conditions

Abstract

for solar light injection and charges collection, the flexibility of which is also beneficial for the development of bendable and flexible photovoltaic devices. [9-12] The silver nanowire (AgNW) based transparent electrode with the merits of low-temperature solution-processed fabrication, outstanding optical/electrical property, and superior mechanical flexibility has been also adopted as the bottom or top electrode of perovskite solar cells. [13-18,42] However, the stability of metal electrodes, encountered with the corrosion and failure when adopted in organicinorganic perovskite solar cells, has been considered as the critical issue for their future application in this promising photovoltaic technique. [14,19] In addition, the reaction of halogen species from perovskite layer with metal electrode will also bring irreversible deterioration of the device performance. [20-22] Inserting electrical conductive and physical blocking material between the metal electrode and perovskite film has been proposed to improve the stability of metal electrode and the device performance. [23-26] Despite previous reports have mentioned various conditions, such as moisture, light, oxygen, etc., are critical to the stability of perovskite device, [27-31] less paper systematically study the corrosion of metal electrode by perovskite film and conventional halogen compounds for the precursor under different environmental conditions. In this paper, we would like to investigate the corrosion against the silver nanowire based transparent electrode by six halogen compounds of CH 3 NH 3 X (MAX) and PbX 2 (X = I, Br, Cl) and the perovskite film of CH 3 NH 3 PbI 3 (MAPbI 3) without and with holes transporting layer under four different environmental conditions, through monitoring the resistance variation of the electrode. The four conditions are set to be a dry nitrogen gas environment without light, dry nitrogen gas environment with light irradiation, wet nitrogen gas without light and nitrogen/oxygen mixture gas without light. X-ray diffraction (XRD) is also adopted to characterize the silver nanowire electrode after electrical resistance characterization. Experimental results demonstrate that both moisture and oxygen will promote the corrosion of MAI against the silver nanowire, as compared with the case of electrode under light irradiation. Since metal electrode is an important component in the perovskite solar cells, which can be used as back contact, transparent electrode, and the transparent interlayer of tandem devices, the corrosion of metal electrode by perovskite film, should be understood. Here, the corrosion of conventional reagents of organic-inorganic perovskite material, i.e., CH 3 NH 3 X (MAX) and PbX 2 , X = I, Br, and Cl, against silver nanowire (AgNW) based transparent electrode are investigated under four different environments, i.e., nitrogen protection, light irradiation, oxygen exposure, and moisture exposure, separately. The corrosion process is inspected by monitoring the time-dependent resistance variation of the ...

A review of silver nanowire-based composites for flexible electronic applications

“…Ag NWs become oxidized and sulfurized in the presence of oxygen, water, and gases such as hydrogen sulphide. The wires can also react with organic molecules and dissolve in water to form Ag + [39,40]. In the case of the composite, the chemically stable GO protects and prevents the NWs from exposure to the environment and prevents oxide formation [267].…”

“…While most flexible applications do not operate above 150 • C (primarily due to substrate limitations) the poor thermal stability does create a processing limitation. Similarly, long term exposure of Ag NWs to ambient conditions can also cause a degradation in their functional properties [39,40]. These factors necessitate various solutions to improve the suitability of Ag NWs for flexible device applications.…”