J. Mater. Sci. Technol. ›› 2026, Vol. 257: 26-33.DOI: 10.1016/j.jmst.2025.08.034

• Research Article • Previous Articles     Next Articles

S-scheme Mo-WO3/CeO2 microspheres photoanode enabling high-efficiency power generation in H2O2 photoelectrochemical cell

Yutong Liua, Yingying Guana, Xiaosong Hana, Yang Zhaoa,*, Hua Songa, Ju Won Lim*, Huan Wanga,*   

  1. aCollege of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing 163318, China;
    bGeorge W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta 30332, GA, USA;
    cDivision of Semiconductor and Electronics Engineering, Hankuk University of Foreign Studies, Yongin 17035, South Korea
  • Received:2025-06-03 Revised:2025-07-15 Accepted:2025-08-06 Online:2025-09-09
  • Contact: *E-mail addresses: yzhao@nepu.edu.cn (Y. Zhao), jwlim@hufs.ac.kr (J.W. Lim), wanghuan83214@gmail.com (H. Wang)

Abstract: This study introduces a significant advancement in sustainable energy conversion through a novel hydrogen peroxide (H2O2) photoelectrochemical cell system. By integrating an oxygen vacancy-rich Mo-doped WO3 (Mo-WO3)/CeO2 S-scheme heterojunction photoanode with a cornstalk-derived porous carbon/Fe-phthalocyanine (PC/FeIIPc) cathode, the system achieves efficient solar-driven H2O2 production and direct electricity generation via in situ H2O2 fuel utilization. The Mo-WO3/CeO2 heterojunction synergizes with Mo doping-induced oxygen vacancies (OVs) and S-scheme charge transfer pathways, significantly enhancing light absorption and charge separation. This design enables a remarkable H2O2 yield of 0.044 M and a maximum power density of 5.79 mW cm-2, surpassing the pristine WO3-based cell by 4 and 2.55 times, respectively. Additionally, the cell exhibits robust dark-phase energy storage with a capacitance of 57,834 mF cm-2, which has a 54% capacity retention over 12 h. Combined experimental and theoretical analyses reveal that oxygen vacancies in Mo-WO3 act as electron traps, while the S-scheme heterojunction’s internal electric field directs charge flow, collectively suppressing recombination and preserving redox potentials. This work establishes a green paradigm for simultaneous solar energy harvesting, chemical fuel storage, and on-demand electricity generation.

Key words: S-scheme heterojunction, Mo-doped WO3, CeO2 quantum dot, H2O2 photoelectrochemical cell, Solar-to-fuel-to-electric conversion