Highly Active Hierarchical Au Nanoparticles/Cellulose@TiO2 Prepared by Surface Charge Assisted Self-Assembly

The catalyst Au/cellulose@TiO(2) with a hierarchical structure was one-pot synthesized by conventional deposition-precipitation urea method. Nanosized TiO(2) particles, instead of self-agglomeration, homogeneously dispersed on the microsized microcrystalline cellulose. Simultaneously, gold particles with particle size of about 3.4 nm were mainly well-deposited on TiO(2) particles. It was found that the surface charges of TiO(2), cellulose and gold species played a key role in assisting in selfassembling them into the hierarchical structure. p-nitrophenol hydrogenation results displayed that the catalytic activity of Au/cellulose@TiO(2) was 1.8 times and 10.9 times higher than that of Au/TiO(2) and Au/cellulose, respectively. The improvement in catalytic performance of Au/cellulose@TiO(2) was closely related to its hierarchical structure that influenced mass transfer of reactants and recycle of catalysts.