Photothermal catalysis enhances cellulose oxidation kinetics to promote the hydrogen evolution in alkaline solution over Pt/ZnIn2S4

The slow oxidation kinetics of cellulose severely limits photocatalytic cellulose reforming for hydrogen production. Herein, ZIS photocatalysts with different morphologies were prepared and Pt nanoparticles were deposited on their surfaces. The cellulose oxidation kinetics were enhanced through the strategy of photothermal catalysis and pH optimization, which led to efficient hydrogen generation. The ultrathin nanosheet structure endows 1 % Pt/ZIS-300 with a stronger photogenerated carrier separation ability than 1 % Pt/ZIS-0 (nanoflower) and facilitates & sdot;OH generation. Heat can induce the production of & sdot;OH from 1 % Pt/ZIS-300 and enhance the adsorption of 1 % Pt/ZIS-300 to cellulose by changing the surface potential of 1 % Pt/ZIS-300, which promotes the oxidation kinetics of cellulose. As a result, the hydrogen yield of 1 % Pt/ZIS-300 under photothermal catalytic condition (80 degree celsius) reached 1218 mu mol/gcat after 4 h of reaction. Appropriate NaOH concentration contributes to cellulose solubilization and & sdot;OH production, but too high OH- concentration causes a negative shift of the potential on the 1 % Pt/ZIS-300 and cellulose surface, which hinders the mass transfer process and reduces the oxidation kinetics of cellulose.