Department of Chemistry, University of California and Chemical Sciences and Materials, Sciences Divisions, Lawrence Berkeley National Lab., Berkeley, CA 94720, USA.
Department of Chemistry, University of California and Chemical Sciences and Materials, Sciences Divisions, Lawrence Berkeley National Lab., Berkeley, CA 94720, USA.
J Colloid Interface Sci. 2013 Feb 15;392:122-128. doi: 10.1016/j.jcis.2012.10.029. Epub 2012 Nov 8.
Mesoporous SiO(2), Al(2)O(3), TiO(2), Nb(2)O(5), and Ta(2)O(5) were synthesized through a soft-templating approach by a self-assembled framework of Pluronic P123 and utilized for the preparation of 3-dimensional catalysts as supports. Colloidal Pt nanoparticles with an average diameter of 1.9 nm were incorporated into the mesoporous oxides by sonication-induced capillary inclusion. The Pt nanoparticles supported on mesoporous oxides were evaluated in the hydrogenation reaction of furfural (70 torr furfural and 700 torr H(2) with a balance of He) to study the effect of catalyst supports on selectivity. In the temperature ranges of 170-240°C, the major products of this reaction were furan, furfuryl alcohol, and 2-methyl furan through a main reaction pathway of either decarbonylation or carbonyl group hydrogenation. While Pt nanoparticles with the size ranges of 1.5-7.1 exhibited strong structure-dependent selectivity, various supports loaded with only 1.9 nm Pt nanoparticles produced dominantly furan as a major product. Compared to the inert silica support, TiO(2) and Nb(2)O(5) facilitated an increase in the production of furfuryl alcohol via carbonyl group hydrogenation as a result of a charge transfer interaction between the Pt and the acidic surface of the oxides. The same trend was confirmed on 2-dimensional type catalysts, in which thin films of SiO(2), Al(2)O(3), TiO(2), Nb(2)O(5), and ZrO(2) were prepared as supports. When furfural hydrogenation was conducted (1 torr furfural, 100 torr H(2), and 659 torr He) over Pt nanoparticle monolayers deposited on oxide substrates, only TiO(2) was shown to increase the production of furfuryl alcohol, while other oxides produced furan.
介孔二氧化硅、氧化铝、二氧化钛、五氧化二铌和五氧化二钽通过 Pluronic P123 的自组装骨架采用软模板法合成，并用作 3 维催化剂载体。通过超声诱导的毛细包含将平均直径为 1.9nm 的胶体 Pt 纳米粒子掺入介孔氧化物中。将 Pt 纳米粒子负载在介孔氧化物上，用于糠醛（70torr 糠醛和 700torr H2，其余为 He）加氢反应，以研究催化剂载体对选择性的影响。在 170-240°C 的温度范围内，该反应的主要产物是呋喃、糠醇和 2-甲基呋喃，通过脱羰或羰基加氢的主要反应途径。虽然 1.5-7.1nm 范围内的 Pt 纳米粒子具有强烈的结构依赖性选择性，但负载仅 1.9nmPt 纳米粒子的各种载体主要生成呋喃作为主要产物。与惰性二氧化硅载体相比，TiO2 和 Nb2O5 通过 Pt 和氧化物酸性表面之间的电荷转移相互作用促进了羰基加氢生成糠醇的增加。在二维类型的催化剂上也证实了相同的趋势，其中作为载体的 SiO2、Al2O3、TiO2、Nb2O5 和 ZrO2 的薄膜被制备。当在氧化物衬底上沉积的 Pt 纳米粒子单层上进行糠醛加氢反应（1torr 糠醛、100torr H2 和 659torr He）时，仅 TiO2 显示出增加糠醇的生成，而其他氧化物生成呋喃。
