Fig. 3: Photocatalytic C−N coupling for glycine production.
From: Glycine photosynthesis via C−N coupling of waste plastic and nitrate over diatomic Pd−B catalyst
a Schematic illustration of the photocatalytic synthesis of glycine from EG and nitrate. The blue sphere represents the N element, the gray sphere represents the C element, the red sphere represents the O element, and the white sphere represents the H element. The arrow represents conversion or formation. b Glycine production rates over various types of semiconductors. c Glycine production rates over various metal single-atom anchored BCNx catalysts, including Pt, Pd, Au, Ag, Cu, Co and Fe. Reaction conditions: 20 mg photocatalyst, 50 mL 0.1 M EG/0.5 M NO3− solution, T = 25 °C, Ar atmosphere, t = 24 h, and 300 W Xe lamp (320 nm < λ < 780 nm). d The yield of glycine within 24 h under various reaction conditions. Not detected represents the product could not be detected due to exceeding the detection limit of the instrument. e Control experiments of BCNx with different Pd loadings in 0.5 M KNO3 and different concentrations of KNO3 over Pd SA/BCNx (1 wt% Pd). f The yield of glycine within 24 h over Pd SA/CN, BCNx and Pd SA/BCNx. The left Y-axis represents glycine accumulation, and the right Y-axis represents selectivity. These dashed arrows represent multiples of growth. g Evaluation of recycling stability. h 1H NMR spectra during the photocatalytic reaction. i Long-term accumulation profiles for glycine produced over Pd SA/BCNx. The dashed arrow represents glycine accumulation. j Schematic diagram of EG photoconversion to glycine in PET hydrolysate over Pd SA/BCNx. k Glycine products derived from the reaction through gas chromatography−mass spectrometry (GC‒MS) analyses. The arrow represents the direction towards glycine. Error bars represent the standard deviations from the means of at least three repeated experiments.
