Dual Influence of Reduction Annealing on Diffused Hematite/FTO Junction for Enhanced Photoelectrochemical Water Oxidation.
Band structure engineering of the interface between the semiconductor and the conductive substrate may profoundly influence charge separation and transport for photovoltaic and photoelectrochemical devices. In this work, we found that a reduction-annealing treatment resulted in a diffused junction through enhanced interdiffusion of hematite/FTO at the interface. The activated hematite exhibited higher nanoelectric conductivity that was probed by a PeakForce TUNA AFM method. Furthermore, charge accumulation and recombination via surface states at the interface were dramatically reduced after the reduction-annealing activation, which was confirmed by transient surface photovoltage measurements. The diffused hematite junction promises improved photoelectrochemical performance without the need for a buffer layer.
Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University , Xuchang, Henan 461000, P. R. China.
Xiaogang
X
Yang
Joint Center for Artificial Photosynthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Rui
R
Liu
Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University , Xuchang, Henan 461000, P. R. China.
Yan
Y
Lei
Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University , Xuchang, Henan 461000, P. R. China.
Pinjiang
P
Li
Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University , Xuchang, Henan 461000, P. R. China.
Ke
K
Wang
Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, Xuchang University , Xuchang, Henan 461000, P. R. China.
Zhi
Z
Zheng
Department of Chemistry, Merkert Chemistry Center, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.
Dunwei
D
Wang
diffused junction; hematite/FTO interface; nanoelectric conductivity; reduction-annealing activation; transient surface photovoltage