Improved photocatalytic activity of LaFeO3 with doping Mn3+ ions and modifying Pd2+ ions for photoreduction of CO2 into CH4

• Published in: Journal of power sources Vol. 519; p. 230738
• Main Authors: Shi, Zhaojun, Li, Hanbo, Zhang, Lixin, Cao, Yaan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31.01.2022
• Subjects: Photocatalytic activity; Photocatalytic mechanism; Surface species; Synergistic effect; Photocatalytic activity; Photocatalytic mechanism; Synergistic effect; Surface species
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2021.230738

A new type of Mn-doped and Pd-modified LaFeO3 (LaFeO3-Mn-Pd) photocatalyst is introduced by a sol-gel method. The existing states of dopants (Mn and Pd), the band structures, and the behaviors of photogenerated carriers for LaFeO3-Mn-Pd are studied. It is revealed that the Mn3+ ions are doped into the LaFeO3 lattice by substituting Fe3+ ions, while the Pd2+ ions exist as -O-Pd-Cl species on the surface of LaFeO3. The Mn3+ ions and -O-Pd-Cl species increase the absorption of light. Moreover, a more suitable band structure for the redox potential of CO2 conversion into CO and CH4, and higher carrier separation efficiency appeared. The Mn3+ ions promote the conversion of CO2 into CO for LaFeO3-Mn, while the -O-Pd-Cl surface species boost the conversion of CO into CH4 for LaFeO3-Pd. Furthermore, the synergistic effect of Mn3+ ions and -O-Pd-Cl species realize the conversion of CO2 into CH4 and improve the photocatalytic activity of LaFeO3-Mn-Pd effectively. These results offer a paradigm for the design and fabrication of novel LaFeO3-based photocatalysts with excellent photocatalytic performance. •The introduced Mn3+ are doped into the LaFeO3 in mode of substituting Fe3+.•The introduced Pd2+ form –O–Pd–Cl species on the surface of LaFeO3.•The Mn-doped and Pd-modified on LaFeO3 can improve the visible light absorption.•The Mn-doped and Pd-modified on LaFeO3 can promote separation of carriers.•The synergistic effect of Mn3+ and Pd2+ ions can improve photocatalytic activity.