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Indexed by:期刊论文

Date of Publication:2017-01-01

Journal:NANO ENERGY

Included Journals:SCIE、EI

Volume:31

Page Number:424-431

ISSN No.:2211-2855

Key Words:Low temperature; Flexible solar cells; Amorphous; Electron selective layer; Perovskite solar cells

Abstract:Flexible perovskite solar cell (PSC) using plastic substrate is one of the most focal points in the studies of thinfilm solar cells. Low-temperature preparation of suitable electron selective layer (ESL) is the key issue in the fabrication of flexible PSCs. In this work, amorphous niobium-modified tungsten oxide W(Nb)O-x was prepared as ESL for efficient flexible PSC. Modification using Nb+ improved the electron transport of WOx-based ESL by enhancing donor density, reducing interfacial depletion width, and minimizing trap states in the ESL. Consequently, photovoltaic performance of the simple planar flexible PSCs was improved, and high PCEs of 15.65% and 13.14% were obtained when ESLs were fabricated at 120 degrees C and room temperature, respectively. In addition, the effect of ESL thickness on the hysteresis behavior of PSCs was carefully analyzed. A capacitance C-E across the ESL in the ITO/ESL/perovskite structure was proposed. This capacitance could well indicate the effect of ESL thickness on hysteresis behavior. The proposed modification strategy and mechanism is expected to facilitate the development of novel and advanced functional materials.