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Chiral-Induced Spin Selectivity Steering OH-to-OOH Conversion for Efficient Photoelectrochemical Water Splitting
Zhiang Hou1, Rui Hu1, Yitong Chen1
1State Key Laboratory of Water Pollution Control and Green Resource Recycling, School of Environment, Nanjing University, Nanjing, Jiangsu, China.
Small (Weinheim an Der Bergstrasse, Germany)
|June 8, 2026
Summary
Chiral catalysts enhance photoelectrochemical water splitting by controlling electron spin states. This spin selectivity accelerates oxygen evolution reactions and improves photoanode stability and efficiency.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- The four-electron oxygen evolution reaction (OER) is crucial for water splitting but limited by oxygen intermediate spin states.
- Efficient photoelectrochemical water splitting requires overcoming these spin state limitations.
Purpose of the Study:
- To design a chiral photoanode utilizing the chiral-induced spin selectivity (CISS) effect to improve OER efficiency.
- To investigate the mechanism by which spin alignment influences OER pathways and intermediate formation.
Main Methods:
- Fabrication of a chiral L-Co(3-x)NixO4/BiVO4 photoanode with a chiral co-catalyst layer.
- Kinetic isotope experiments, in situ attenuated total reflection Fourier Transform infrared spectroscopy (ATR-FTIR).
- Density functional theory (DFT) calculations.
Main Results:
- The chiral photoanode demonstrated facilitated conversion of *OH to *OOH intermediates via spin-state alignment.
- Suppression of hydrogen peroxide formation (Faradaic efficiency < 10%) and enhanced photoanode stability (>100 h).
- Achieved a photocurrent density of 5.41 mA·cm⁻² at 1.23 V vs. RHE.
Conclusions:
- The CISS effect can be leveraged to control OER pathways and intermediate formation.
- Spin-engineering offers a viable route for developing efficient and stable photoanodes for water splitting.
- The L-Co(3-x)NixO4/BiVO4 photoanode represents a significant advancement in solar fuel technology.
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