Solvent-Free Selective Catalytic Oxidation of Benzyl Alcohol over Pd/g-C3N4: Exploring the Structural Impact of g-C3N4

A series of Pd/g-C3N4 catalysts were synthesized using different graphitic carbon nitride precursors, and were found to exhibit significant variations in catalytic performance for solvent-free selective catalytic oxidation of benzyl alcohol. Through comprehensive characterization (XRD, N2-BET, ICP-AES, TEM, and XPS), the experimental results found that the nitrogen chemical configuration and surface Pd2+concentration critically determined the catalytic efficiency. Among the various nitrogen species, N-(C)3-type nitrogen demonstrated the strongest influence on catalytic activity, which was positively correlated with its abundance in g-C3N4 matrices. In particular, g-C3N4 derived from dicyandiamide contained the highest N-(C)3 type nitrogen content. When serving as Pd nanoparticle support, this material simultaneously achieved the best Pd2+ surface concentration and catalytic performance compared to the other g-C3N4-supported catalysts.