Spatially Confined Formation of Single Atoms in Highly Porous Carbon Nitride Nanoreactors.

Reducing the size of a catalyst to a single atom (SA) level can dramatically change its physicochemical properties and significantly boost its catalytic activity. However, the massive synthesis of SA catalysts still remains a grand challenge mainly because of the aggregation and nucleation of the generated atoms during the reaction. Here, we design and implement a spatially confined synthetic strategy based on a porous-hollow carbon nitride (-CN) coordinated with 1-butyl-3-methylimidazole hexafluorophosphate, which can act as a nanoreactor and allow us to obtain metal SA catalysts (-CN@M SAs). This relatively easy and highly effective method provides a way to massively synthesize single/multiple atoms (-CN@M SAs, M = Pt, Pd, Cu, Fe, .). Moreover, the amorphous NiB-coated -CN@Pt SAs can further increase the loading amount of Pt SAs to 3.7 wt %. The synthesized -CN@Pt&NiB electrocatalyst exhibits an extraordinary hydrogen evolution reaction activity with the overpotential of 40.6 mV@10 mA/cm and the Tofel slope of 29.26 mV/dec.