A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventiona...A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventional method, the new catalysts prepared via the new method exhibit much higher BET surface area and pore size, much smaller crystallite size and higher catalytic activity and selectivity in CO 2 hydrogenation to methanol. It is also found that the molar ratio of Cu + to Cu 0 on the surface of the catalyst obtained by coprecipitation-reduction is much higher than that on the reduced catalyst obtained by the conventional method, which could be crucial for its high activity and selectivity for catalytic hydrogenation of CO 2 to methanol.展开更多
用溶胶-凝胶法制得Cu/Fe2O3-TiO2光催化材料。用XRD、Ram an、TPR、IR、TEM、UV-V is DRS测试技术和光催化反应等对固体材料的结构和性能进行了表征。结果表明,Fe2O3的质量分数为10%时,在TiO2表面以单分子层分散,Fe2O3的引入使TiO2吸光...用溶胶-凝胶法制得Cu/Fe2O3-TiO2光催化材料。用XRD、Ram an、TPR、IR、TEM、UV-V is DRS测试技术和光催化反应等对固体材料的结构和性能进行了表征。结果表明,Fe2O3的质量分数为10%时,在TiO2表面以单分子层分散,Fe2O3的引入使TiO2吸光限蓝移。Fe2O3含量超过单分子层分散时,有晶相Fe2O3生成,光吸收性能下降。Fe—O—Ti键的形成加强了半导体之间的相互作用,有利于光生载流子在半导体间的输送。少量Cu的引入,使复合材料的吸光域向可见光范围扩展。光催化反应性能与材料的光响应能力密切相关。在光催化CO2和CH3NH2直接合成NH2CH2COOH的反应中,负载质量分数为10%Fe2O3的光催化反应性能最优。在120℃、常压、空速200 h-1、CO2与CH3NH2摩尔比为1∶1和6.5×10-4W/cm2的紫外灯照射下,CH3NH2转化率为1.35%,NH2CH2COOH选择性达92.0%。展开更多
制备了Fe(bpy)32+负载偕胺肟改性聚丙烯腈(PAN)纤维非均相Fenton催化剂,并通过配位作用将Cu2+引入该催化剂,制备了双金属负载改性PAN纤维催化剂(Cu Fe B-PAN)。并对该催化剂进行FTIR光谱、UV-Vis DRS谱图、光催化活性分析,探讨并分析了...制备了Fe(bpy)32+负载偕胺肟改性聚丙烯腈(PAN)纤维非均相Fenton催化剂,并通过配位作用将Cu2+引入该催化剂,制备了双金属负载改性PAN纤维催化剂(Cu Fe B-PAN)。并对该催化剂进行FTIR光谱、UV-Vis DRS谱图、光催化活性分析,探讨并分析了不同因素对光催化活性的影响。结果表明,Cu2+的引入拓宽了催化剂的可见光吸收范围;Cu2+的引入明显提高了催化剂的光催化活性,而且拓宽了p H适用范围;Cu2+的引入提高了催化剂对可见光的利用效率。展开更多
文摘A novel coprecipitation-reduction process has been proposed for preparing highly selective Cu/ZnO/Al 2O 3 catalysts for methanol synthesis from CO 2 hydrogenation. Compared to the catalysts prepared by the conventional method, the new catalysts prepared via the new method exhibit much higher BET surface area and pore size, much smaller crystallite size and higher catalytic activity and selectivity in CO 2 hydrogenation to methanol. It is also found that the molar ratio of Cu + to Cu 0 on the surface of the catalyst obtained by coprecipitation-reduction is much higher than that on the reduced catalyst obtained by the conventional method, which could be crucial for its high activity and selectivity for catalytic hydrogenation of CO 2 to methanol.
文摘用溶胶-凝胶法制得Cu/Fe2O3-TiO2光催化材料。用XRD、Ram an、TPR、IR、TEM、UV-V is DRS测试技术和光催化反应等对固体材料的结构和性能进行了表征。结果表明,Fe2O3的质量分数为10%时,在TiO2表面以单分子层分散,Fe2O3的引入使TiO2吸光限蓝移。Fe2O3含量超过单分子层分散时,有晶相Fe2O3生成,光吸收性能下降。Fe—O—Ti键的形成加强了半导体之间的相互作用,有利于光生载流子在半导体间的输送。少量Cu的引入,使复合材料的吸光域向可见光范围扩展。光催化反应性能与材料的光响应能力密切相关。在光催化CO2和CH3NH2直接合成NH2CH2COOH的反应中,负载质量分数为10%Fe2O3的光催化反应性能最优。在120℃、常压、空速200 h-1、CO2与CH3NH2摩尔比为1∶1和6.5×10-4W/cm2的紫外灯照射下,CH3NH2转化率为1.35%,NH2CH2COOH选择性达92.0%。
文摘制备了Fe(bpy)32+负载偕胺肟改性聚丙烯腈(PAN)纤维非均相Fenton催化剂,并通过配位作用将Cu2+引入该催化剂,制备了双金属负载改性PAN纤维催化剂(Cu Fe B-PAN)。并对该催化剂进行FTIR光谱、UV-Vis DRS谱图、光催化活性分析,探讨并分析了不同因素对光催化活性的影响。结果表明,Cu2+的引入拓宽了催化剂的可见光吸收范围;Cu2+的引入明显提高了催化剂的光催化活性,而且拓宽了p H适用范围;Cu2+的引入提高了催化剂对可见光的利用效率。
