Metallic Powder Promotes Nitridation Kinetics for Facile Synthesis of (oxy)nitride Photocatalysts.

Nitrogen-containing semiconductors (including metal nitrides, metal oxynitrides, and nitrogen-doped metal oxides) have been widely researched for their application in energy conversion and environmental purification because of their unique characteristics; however, their synthesis generally encounters significant challenges owing to sluggish nitridation kinetics. Herein, we have developed a metallic powder-assisted nitridation method that effectively promotes the kinetics of nitrogen insertion into oxide precursors and exhibits good generality. By employing metallic powders with low work functions as electronic modulators, a series of oxynitrides (i.e., LnTaON 2 (Ln = La, Pr, Nd, Sm, and Gd), Zr 2 ON 2 , and LaTiO 2 N) can be prepared at lower nitridation temperatures and shorter nitridation periods to obtain comparable or even lower defect concentrations compared to those of the conventional thermal nitridation method, leading to superior photocatalytic performance. Moreover, some novel nitrogen-doped oxides (i.e., SrTiO 3- x N y and Y 2 Zr 2 O 7- x N y ) with visible-light responses can be exploited. As revealed by density functional theory (DFT) calculations, the nitridation kinetics are enhanced via the effective electron transfer from the metallic powder to the oxide precursors, reducing the activation energy of nitrogen insertion. The modified nitridation route developed herein is an alternative method for preparing (oxy)nitride-based materials for energy/environment-related heterogeneous catalysis. This article is protected by copyright. All rights reserved.