Single Au atoms anchoring on amino-group enriched graphitic carbon nitride for photocatalytic CO2 reduction.

Due to the maximum atom-utilization efficiency and excellent catalytic properties, Au single atom catalysts (SACs) have been extensively studied in various catalytic systems. However, the performance of Au SACs on CO 2 reduction were seldom investigated. Herein, Au single atoms on amino-group modified graphitic carbon nitride (U-ACN) was successfully synthesized through a mild and eco-friendly urea reduction method. U-ACN shows a remarkable performance for CO 2 reduction, with CO and CH 4 yield to be 1.97 and 4.15 times that of pure graphitic carbon nitride under 2.5 h visible light irradiation. The excellent catalytic activity of U-ACN derives from the introduction of Au single atoms, which lower the energy barrier of CH 4 formation, narrow the bandgap, and hinder the recombination of charge carriers. In addition, the U-ACN has improved CO 2 affinity due to the urea-introduced amino-groups in the catalysts.