Synergetic effect of Ni-Au bimetal nanoparticles on urchin-like TiO2 for hydrogen and arabinose co-production by glucose photoreforming

Biomass photoreforming is a prospective and attractive strategy to kill two birds with one stone for not only producing hydrogen (H-2) but also valorizing biomass by exploiting infinite solar energy. Here, we design Ni-Au bimetal nanoparticles modified urchin-like TiO2 photocatalysts (NiAu/TiO2) and demonstrate an enhanced glucose photoreforming. The H-2 production rate of the optimal Ni0.05Au0.45/TiO2 (6391.86 mu mol h(-1) g(-1)) is 118.57, 30.78, and 1.65 times of pure TiO2 (53.91 mu mol h(-1) g(-1)), Ni-0.5/TiO2 (207.56 mu mol h(-1) g(-1)), and Au-0.5/TiO2 (3867.12 mu mol h(-1) g(-1)), respectively. Meanwhile, the glucose conversion rate and the corresponding arabinose selectivity over Ni0.05Au0.45/TiO2 are up to 95.00% and 36.54% after 4-h photoreforming, which are higher than the corresponding monometallic and pristine TiO2. The synergistic effect of Ni and Au nanoparticles, including the localized surface plasmon resonance (LSPR) and Schottky junction of Au nanoparticles and the promoting effect of Ni particles on C-C cleavage in glucose, as well as the three-dimensional hierarchical urchin-like TiO2, significantly improve the H-2 production, glucose conversion, and arabinose selectivity. The research paves a new way to the great potential of bimetal nanoparticles in biomass photoreforming.