Single‐Atom Catalysts on C<sub>3</sub>N<sub>4</sub>: Minimizing Single Atom Pt Loading for Maximized Photocatalytic Hydrogen Production Efficiency
Nawres Lazaar, Si‐Ming Wu, Shanshan Qin, Abdessalem Hamrouni, Bidyut Bikash Sarma, Dmitry E. Doronkin, Nikita Denisov, Hinda Lachheb, Patrik Schmuki
Abstract
Abstract The use of metal single atoms (SAs) as co‐catalysts on semiconductors has emerged as a promising technology to enhance their photocatalytic hydrogen production performance. In this study, we describe the deposition of very low amounts of Pt SAs (<0.1 at %) on exfoliated graphitic carbon nitride (C 3 N 4 ) by a direct Pt−deposition approach from highly dilute chloroplatinic acid precursors. We find that − using this technique−a remarkably low loading of highly dispersed Pt SAs (0.03 wt %) on C 3 N 4 is sufficient to achieve a drastic decrease in the overall charge transfer resistance and a maximized photocatalytic efficiency. The resulting low‐loaded Pt SAs/C 3 N 4 provides a H 2 production rate of 1.66 m mol/h/mg Pt, with a remarkable stability against agglomeration; even during prolonged photocatalytic reactions no sign of light‐induced Pt agglomerations can be observed. We ascribe the high performance and stability to the site‐selective, stable coordination of Pt within the C 3 N 4 structure. Notably the H 2 production rate of the low‐loaded Pt SAs surpasses the activity of Pt SAs deposited by other techniques or nanoparticles at comparable or even higher loading – the optimized Pt SAs decorated C 3 N 4 show ≈5.9 times higher rate than Pt NP decorated C 3 N 4 .