Enhancing photoelectrochemical performance and stability of Ti-doped hematite photoanode via pentanuclear Co-based MOF modification

• Published in: Frontiers in chemistry Vol. 12; p. 1454524
• Main Authors: Dong, Guofa, Xie, Fengyan, Kou, Fangxia, Chen, Tingting, Xiao, Caihong, Du, Shaowu, Liang, Jiaqi, Lou, Chenfang, Zhuang, Jiandong
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 30.08.2024
• Subjects: Co-MOF; hematite; photoelectrochemical water oxidation; polynuclear; Ti doping; hematite; Ti doping; photoelectrochemical water oxidation; Co-MOF; polynuclear
• ISSN: 2296-2646; 2296-2646
• DOI: 10.3389/fchem.2024.1454524

Modifying photoanodes with metal-organic frameworks (MOFs) as oxygen evolution reaction (OER) cocatalysts has emerged as a promising approach to enhance the efficiency of photoelectrochemical (PEC) water oxidation. However, designing OER-active MOFs with both high photo- and electrochemical stability remains a challenge, limiting the advancement of this research. Herein, we present a facile method to fabricate a MOF-modified photoanode by directly loading a pentanuclear Co-based MOF (Co-MOF) onto the surface of a Ti-doped hematite photoanode (Ti:Fe O ). The resulting Co-MOF/Ti:Fe O modified photoanode exhibits an enhanced photocurrent density of 1.80 mA∙cm at 1.23 V, surpassing those of the Ti:Fe O (1.53 mA∙cm ) and bare Fe O (0.59 mA∙cm ) counterparts. Additionally, significant enhancements in charge injection and separation efficiencies, applied bias photon-to-current efficiency (ABPE), incident photon to current conversion efficiency (IPCE), and donor density (N ) were observed. Notably, a minimal photocurrent decay of only 5% over 10 h demonstrates the extraordinary stability of the Co-MOF/Ti:Fe O photoanode. This work highlights the efficacy of polynuclear Co-based MOFs as OER cocatalysts in designing efficient and stable photoanodes for PEC water splitting applications.