NiO nanosheets as efficient top hole transporters for carbon counter electrode based perovskite solar cells

Abstract

Herein, we present fully printable carbon electrode based perovskite solar cells using highly crystalline NiO nanosheets as top hole transport layers, mesoporous TiO₂ nanoparticles as a bottom electron transport layer and ZrO₂ as an intermediate spacer layer, respectively. Time-resolved photoluminescence decay measurements, electron impedance spectroscopy and transient photovoltage decay measurements have revealed that the NiO nanosheets as top hole transporters exhibit superior charge collection efficiency and a prolonged charge lifetime. As a result, an impressive power conversion efficiency of 14.2% is achieved under standard testing conditions.