Nonstoichiometric In–S group yielding efficient carrier transfer pathway in In2S3 photoanode for solar water oxidation
Runyu Chen,
Linxing Meng,
Changda Wang,
Weiwei Xu,
Yulong Huang,
Li Song,
Liang Li
Affiliations
Runyu Chen
School of Physical Science and Technology Jiangsu Key Laboratory of Thin Films Center for Energy Conversion Materials & Physics Soochow University Suzhou Jiangsu P. R. China
Linxing Meng
School of Physical Science and Technology Jiangsu Key Laboratory of Thin Films Center for Energy Conversion Materials & Physics Soochow University Suzhou Jiangsu P. R. China
Changda Wang
National Synchrotron Radiation Laboratory CAS Center for Excellence in Nanoscience University of Science and Technology of China Hefei Anhui P. R. China
Weiwei Xu
School of Electronic and Information Engineering Changshu Institute of Technology Changshu Jiangsu P. R. China
Yulong Huang
School of Physical Science and Technology Jiangsu Key Laboratory of Thin Films Center for Energy Conversion Materials & Physics Soochow University Suzhou Jiangsu P. R. China
Li Song
National Synchrotron Radiation Laboratory CAS Center for Excellence in Nanoscience University of Science and Technology of China Hefei Anhui P. R. China
Liang Li
School of Physical Science and Technology Jiangsu Key Laboratory of Thin Films Center for Energy Conversion Materials & Physics Soochow University Suzhou Jiangsu P. R. China
Abstract The construction of high‐efficiency photoanodes is essential for developing outstanding photoelectrochemical (PEC) water splitting cells. Furthermore, insufficient carrier transport capabilities and sluggish surface water oxidation kinetics limit its application. Using a solvothermal annealing strategy, we prepared a nonstoichiometric In–S (NS) group on the surface of an In2S3 photoanode in situ and unexpectedly formed a type II transfer path of carrier, thereby reducing the interfacial recombination and promoting the bulk separation. First‐principles calculations and comprehensive characterizations demonstrated NS group as an excellent oxygen evolution cocatalyst (OEC) that effectively facilitated carrier transport, lowered the surface overpotential, increased the surface active site, and accelerated the surface oxygen evolution reaction kinetics by precisely altering the rate‐determining steps of * to *OH and *O to *OOH. These synergistic effects remarkably enhanced the PEC performance, with a high photocurrent density of 5.02 mA cm−2 at 1.23 V versus reversible hydrogen electrode and a negative shift in the onset potential by 310 mV. This work provides a new strategy for the in situ preparation of high‐efficiency OECs and provides ideas for constructing excellent carrier transfer and transport channels.
