Among the various types of heterogeneous catalysts,supported metal nanocatalysts(SMNCs)have attracted widespread interest in chemistry and materials science,due to their advantageous features,such as high efficiency,s...Among the various types of heterogeneous catalysts,supported metal nanocatalysts(SMNCs)have attracted widespread interest in chemistry and materials science,due to their advantageous features,such as high efficiency,stability,and reusability for catalytic reactions.However,to obtain well-defined SMNCs and inhibit nanoparticle aggregation,traditional approaches generally involve numerous organic reagents,complex steps,and specialized equipment,thus hindering the practical and large-scale synthesis of SMNCs.In this review,we summarize green and sustainable synthetic methodologies for the assembly of SMNCs,including low temperature pyrolysis and solid-state,surfactant-and reductant-free,and ionic liquid assisted syntheses.The conventional application of SMNCs for electrochemical hydrogen evolution and the corresponding achievements are subsequently discussed.Finally,future perspectives toward the sustainable production of SMNCs are presented.展开更多
The washed and dried porous silica gel was soaked in water glass of moderate viscosity, then mixed with nanometer TiO 2, stired until TiO 2 has been uniformly distributed on the porous silica gel. After dried naturall...The washed and dried porous silica gel was soaked in water glass of moderate viscosity, then mixed with nanometer TiO 2, stired until TiO 2 has been uniformly distributed on the porous silica gel. After dried naturally, it was calcined at 300 ℃ for 1 h to give the immobilized nanometer TiO 2 which was mechanically and chemically stable, and can be reused. Under the illumination of high pressure Hg lamp, the X 3B dye could be degraded almost quantitatively(98%) in a solution containing the photocatalyst, Fe 3+ and H 2O 2 with bubbling of air.展开更多
文摘Among the various types of heterogeneous catalysts,supported metal nanocatalysts(SMNCs)have attracted widespread interest in chemistry and materials science,due to their advantageous features,such as high efficiency,stability,and reusability for catalytic reactions.However,to obtain well-defined SMNCs and inhibit nanoparticle aggregation,traditional approaches generally involve numerous organic reagents,complex steps,and specialized equipment,thus hindering the practical and large-scale synthesis of SMNCs.In this review,we summarize green and sustainable synthetic methodologies for the assembly of SMNCs,including low temperature pyrolysis and solid-state,surfactant-and reductant-free,and ionic liquid assisted syntheses.The conventional application of SMNCs for electrochemical hydrogen evolution and the corresponding achievements are subsequently discussed.Finally,future perspectives toward the sustainable production of SMNCs are presented.
文摘The washed and dried porous silica gel was soaked in water glass of moderate viscosity, then mixed with nanometer TiO 2, stired until TiO 2 has been uniformly distributed on the porous silica gel. After dried naturally, it was calcined at 300 ℃ for 1 h to give the immobilized nanometer TiO 2 which was mechanically and chemically stable, and can be reused. Under the illumination of high pressure Hg lamp, the X 3B dye could be degraded almost quantitatively(98%) in a solution containing the photocatalyst, Fe 3+ and H 2O 2 with bubbling of air.
文摘采用湿法浸渍-辉光放电等离子还原法,制备了MCM-41负载纳米钯催化剂(Pd-WP/M41),并通过XRD、TEM、XPS、H2-TPR和H2-TPD等手段对Pd-WP/M41进行了表征。结果表明:钯纳米粒子(PdNPs)均匀分散在载体MCM-41表面,平均粒径为2.52 nm。与化学还原法制备的催化剂(Pd-WC/M41)相比,Pd-WP/M41上钯的分散度更高,且具有更多的催化活性位点。Pd-WP/M41催化十二氢-N-乙基咔唑(12H-NEC)的脱氢反应实验结果表明,在180℃下反应6 h时,12H-NEC脱氢效率为98.79%,脱氢反应活化能为85.2 k J/mol。Pd-WP/M41循环4次时,12H-NEC脱氢效率仍达到91.23%。
