A Novel Perspective on Enhancing Photocatalytic Performance through the Synergistic Effect of Nd Single Atoms and Heterostructures.

There are few reports on lanthanide single atom modified catalysts, as the role of the 4f levels in photocatalysis is difficult to explain clearly. Here, the synergistic effect of 4f levels of Nd and heterostructures is studied by combining steady-state, transient, and ultrafast spectral analysis techniques with DFT theoretical calculations based on the construction of Nd single atom modified black phosphorus/g-C 3 N 4 (BP/CN) heterojunctions. As expected, the generation rates of CO and CH 4 of the optimized heterostructure are 7.44 and 6.85 times higher than those of CN, and 8.43 and 9.65 times higher than those of BP, respectively. The Nd single atoms can not only cause surface reconstruction and regulate the active sites of BP, but also accelerate charge separation and transfer, further suppressing the recombination of electron-hole pairs. The electrons can transfer from g-C 3 N 4 :Nd to BP:Nd, with a transfer time of ≈11.4 ps, while the radiation recombination time of electron-hole pairs of g-C 3 N 4 is ≈26.13 µs, indicating that the construction of heterojunctions promotes charge transfer. The 2 P 1/2 / 2 G 9/2 / 4 G 7/2 / 2 H 11/2 / 4 F 7/2 → 4 I 9/2 emissions from Nd 3+ can also be absorbed by heterostructures, which improves the utilization of light. The energy change of the key rate measurement step CO 2 * →COOH * decreases through Nd single atom modification.