Fabrication of an Fe‐Doped SrTiO 3 Photocatalyst with Enhanced Dinitrogen Photofixation Performance

• Published in: European journal of inorganic chemistry 2019-04, Vol.2019 (16), p.2182-2192
• Main Authors: Ying, Zihao, Chen, Shengtao, Peng, Tianyou, Li, Renjie, Zhang, Jing
• Format: Article
• Language: English
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201900098

SrTiO 3 as semiconducting photocatalyst has been extensively investigated due to its band edges meeting the thermodynamic requirements for water splitting, but a few attention has been concentrated on its application in the NH 3 synthesis via N 2 photofixation process. Herein, Fe‐doped SrTiO 3 (Fe x Sr 1– x TiO 3 ) products (0 ≤ x ≤ 0.20) were synthesized via a hydrothermal process followed by calcination at 700 °C. All Fe x Sr 1– x TiO 3 products (0.03 ≤ x ≤ 0.20) deliver an enhanced N 2 fixation ability, and Fe x Sr 1– x TiO 3 ( x = 0.10) achieves the best NH 3 production activity of 30.1 µmol g –1 h –1 , which is 3.2‐hold higher than that of SrTiO 3 alone. Once the x value is higher than 0.10, Fe x Sr 1– x TiO 3 will transform into composites containing Fe‐doped SrTiO 3 and α‐Fe 2 O 3 , which acts as charge recombination sites, thus causes a decreased N 2 fixation activity. Further investigations demonstrate that the surface Fe 3+ ‐doped sites can not only chemisorb and activate N 2 molecules, but also promote the interfacial electron transfer from Fe‐doped SrTiO 3 to N 2 molecules, and thus significantly improve the N 2 fixation ability. The present Fe‐doped SrTiO 3 products exhibit characteristic features such as stable and efficient N 2 fixation ability as well as simultaneous realization of N 2 reduction and H 2 O oxidation without co‐catalyst, which are of significance in artificial photosynthesis with H 2 O as electron and proton sources.