Confining single-atom Pd on g-C3N4 with carbon vacancies towards enhanced photocatalytic NO conversion

• Published in: Applied catalysis. B, Environmental Vol. 284; p. 119683
• Main Authors: Liu, Guimei, Huang, Ying, Lv, Haiqin, Wang, Hui, Zeng, Yubin, Yuan, Mingzhe, Meng, Qingguo, Wang, Chuanyi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.05.2021; Elsevier BV
• Subjects: Carbon; Carbon nitride; Catalysts; Catalytic activity; Conversion; Current carriers; Defect; Fabrication; g-C3N4; Metals; Nitrogen atoms; Noble metals; Photocatalysis; Photocatalysts; Photocatalytic NO conversion; Photoluminescence; Photons; Single-atom; Surface defects; Vacancies; g-C3N4; Defect; Photocatalytic NO conversion; Pd; Single-atom
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.119683

The distribution of single-atom Pd on g-C3N4 support can be controlled by constructing surface defects and the fabricated catalysis presents excellent performance for photocatalytic NO conversion. [Display omitted] •Carbon defects are utilized to manipulate the distribution of single-atom Pd.•Prepared Pd-Cv-CN shows high activity and good stability in NO photo-conversion.•The single-atom Pd can facilitate the transportation of the photo-generated electrons. Modification of a photocatalyst with single-atom noble metals can improve its activity while a remaining challenge is the stabilization of single atoms. As a proof of concept, g-C3N4 with desired amount of carbon defects was fabricated to manipulate the distribution of single-atom Pd by taking advantage of its affinity with carbon vacancy-resulted nitrogen atoms. The single-atom Pd was produced by photo-reduction, preferentially located on the carbon vacancy sites as supported by HAADF-STEM and XAFS analyses. As obtained photocatalyst showed high and stable photocatalytic activity in NO conversion; its activity is about 4.4 times higher than that of the pristine g-C3N4. The improved photoactivity was attributed to the preferential separation and transportation of the photo-generated charge carriers due to the introduction of single-atom Pd as evidenced by UV–vis, static and time-resolved photoluminescence spectroscopic analyses. The present work underlines the impetus of surface defect chemistry in the fabrication of single-atom catalysts.