Inorganics (Apr 2023)

In Situ Synthesis of Ti:Fe<sub>2</sub>O<sub>3</sub>/Cu<sub>2</sub>O p-n Junction for Highly Efficient Photogenerated Carriers Separation

  • Tie Shi,
  • Yanmei Feng,
  • Yi Zhong,
  • Hao Ding,
  • Kai Chen,
  • Daimei Chen

DOI
https://doi.org/10.3390/inorganics11040155
Journal volume & issue
Vol. 11, no. 4
p. 155

Abstract

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High photoelectrochemical water oxidation efficiency can be achieved through an efficient photogenerated holes transfer pathway. Constructing a photoanode semiconductor heterojunction with close interface contact is an effective tactic to improve the efficiency of photogenerated carrier separation. Here, we reported a novel photoanode p-n junction of Ti:Fe2O3/Cu2O (n-Ti:Fe2O3 and p-Cu2O), Cu2O being obtained by in situ reduction in CuAl-LDH (layered double hydroxides). The Ti:Fe2O3/Cu2O photoanode exhibits a high photocurrent density reaching 1.35 mA/cm2 at 1.23 V vs. RHE is about 1.67 and 50 times higher than the Ti:Fe2O3 and α-Fe2O3 photoanode, respectively. The enhanced PEC activity for the n-Ti:Fe2O3/p-Cu2O photoelectrode is due to the remarkable surface charge separation efficiency (ηsurface 85%) and bulk charge separation efficiency (ηbulk 72%) formed by the p-n junction and the tight interface contact formed by in situ reduction. Moreover, as a cocatalyst, CuAl-LDH can protect the Ti:Fe2O3/Cu2O photoanode and improve its stability to a certain extent. This study provides insight into the manufacturing potential of in situ reduction layered double hydroxides semiconductor for designing highly active photoanodes in the field of photoelectrochemical water oxidation.

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