Defect density modulation of La2TiO5: An effective method to suppress electron-hole recombination and improve photocatalytic nitrogen fixation

Muyao Song; Lijing Wang; Jiaxin Li; Dewu Sun; Renquan Guan; Hongju Zhai; Xinchun Gao; Xiaohui Li; Zhao Zhao; Zaicheng Sun

doi:10.1016/j.jcis.2021.06.055

Defect density modulation of La₂TiO₅: An effective method to suppress electron-hole recombination and improve photocatalytic nitrogen fixation

J Colloid Interface Sci. 2021 Nov 15:602:748-755. doi: 10.1016/j.jcis.2021.06.055. Epub 2021 Jun 11.

Authors

Muyao Song¹, Lijing Wang², Jiaxin Li¹, Dewu Sun³, Renquan Guan⁴, Hongju Zhai⁵, Xinchun Gao¹, Xiaohui Li¹, Zhao Zhao⁶, Zaicheng Sun⁷

Affiliations

¹ Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education, Jilin Normal University, Changchun 130103, China.
² Henan Engineering Center of New Energy Battery Materials, Henan D&A Engineering Center of Advanced Battery Materials, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
³ Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education, Jilin Normal University, Changchun 130103, China. Electronic address: sundewu1971212@163.com.
⁴ Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education, Jilin Normal University, Changchun 130103, China; Faculty of Chemistry, Northeast Normal University, Changchun 130024, China.
⁵ Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education, Jilin Normal University, Changchun 130103, China. Electronic address: hjzhai1016@163.com.
⁶ Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education, Jilin Normal University, Changchun 130103, China; Faculty of Chemistry, Northeast Normal University, Changchun 130024, China. Electronic address: rbzhao2003@qq.com.
⁷ Center of Excellence for Environmental Safety and Biological Effects, Beijing Key Lab for Green Catalysis and Separation, Department of Chemistry and Biology, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.

PMID: 34171745
DOI: 10.1016/j.jcis.2021.06.055

Abstract

Highly active and efficient photocatalysts are crucial for the exploration of ammonia synthesis because of the serious problem of energy deficiency. La₂TiO₅ (LTO) perovskite materials have great advantages in the field of photocatalytic nitrogen fixation because of the broadly diversified properties. The rational design of surface defect is a valid method to modulate photoinduced charge traps and create defect energy levels, especially it is an effective way to suppress the photoinduced charge recombination. Herein, LTO was obtained by a simple sol-gel method and was further reduced by NaBH₄ to introduce oxygen defect on its surface. UV-vis spectra proved that the surface defects could reduce the band gap value of samples, which is beneficial for improving photocatalytic nitrogen fixation activity. For the best photocatalytic samples with good cycle stability, the nitrogen fixation rate is 158.13 μmol·g^-1·h^-1. The mechanism of photocatalytic nitrogen fixation was proposed by the PL, XPS, and PEC results, which provided possibilities for exploring more promising perovskite catalysts in the field of nitrogen fixation.

Keywords: La(2)TiO(5); Nitrogen fixation; Photocatalysis; Surface modification.

MeSH terms

Ammonia
Catalysis
Electrons*
Nitrogen Fixation*
Recombination, Genetic

Substances

Ammonia