Fig. 5From: S, N Co-Doped Graphene Quantum Dot/TiO2 Composites for Efficient Photocatalytic Hydrogen GenerationUV-vis measurements. a The UV-vis absorption spectrum of the S,N-GQDs. b The corresponding Tauc plot of the S,N-GQDs. c The UV-vis absorption spectra of the P25 and S,N-GQD/P25Back to article page