催化学报
催化學報
최화학보
CHINESE JOURNAL OF CATALYSIS
2010年
4期
466-470
,共5页
施斌斌%姚国新%李国华%郑遗凡
施斌斌%姚國新%李國華%鄭遺凡
시빈빈%요국신%리국화%정유범
碳化钨%二氧化钛%纳米复合材料%电催化活性%对硝基苯酚%协同效应
碳化鎢%二氧化鈦%納米複閤材料%電催化活性%對硝基苯酚%協同效應
탄화오%이양화태%납미복합재료%전최화활성%대초기분분%협동효응
tungsten carbide%titania%nanocomposite%electrocatalytic activity%p-nitrophenol%synergistic effect
以纳米TiO_2为载体,偏钨酸铵为钨源,采用机械化学法与原位还原碳化相结合的方法制备了碳化钨-TiO_2纳米复合材料,并用X射线衍射和扫描电子显微镜等手段对样品的晶相和形貌进行了表征.结果表明,样品颗粒为不规则粒状,并有不同程度的团聚,样品的晶相组成与还原碳化时间有关,主要有金红石相TiO_2,非化学计量比氧化钛(Ti_6O_(11)),W_2C,W_1C和未定名碳化钨.其中,TiO_2粒径18.8~95.6nm,W_2C粒径17.4~24.2 nm,W_1C粒径14.7~15.8 nm.在三电极体系中,采用循环伏安法测定了样品对对硝基苯酚的电催化活性.结果表明,样品的电催化活性与晶相组成有关,且W_1C与TiO_2构成复合材料后,两者之间存在明显的协同效应.这说明TiO_2是W_1C的良好载体.
以納米TiO_2為載體,偏鎢痠銨為鎢源,採用機械化學法與原位還原碳化相結閤的方法製備瞭碳化鎢-TiO_2納米複閤材料,併用X射線衍射和掃描電子顯微鏡等手段對樣品的晶相和形貌進行瞭錶徵.結果錶明,樣品顆粒為不規則粒狀,併有不同程度的糰聚,樣品的晶相組成與還原碳化時間有關,主要有金紅石相TiO_2,非化學計量比氧化鈦(Ti_6O_(11)),W_2C,W_1C和未定名碳化鎢.其中,TiO_2粒徑18.8~95.6nm,W_2C粒徑17.4~24.2 nm,W_1C粒徑14.7~15.8 nm.在三電極體繫中,採用循環伏安法測定瞭樣品對對硝基苯酚的電催化活性.結果錶明,樣品的電催化活性與晶相組成有關,且W_1C與TiO_2構成複閤材料後,兩者之間存在明顯的協同效應.這說明TiO_2是W_1C的良好載體.
이납미TiO_2위재체,편오산안위오원,채용궤계화학법여원위환원탄화상결합적방법제비료탄화오-TiO_2납미복합재료,병용X사선연사화소묘전자현미경등수단대양품적정상화형모진행료표정.결과표명,양품과립위불규칙립상,병유불동정도적단취,양품적정상조성여환원탄화시간유관,주요유금홍석상TiO_2,비화학계량비양화태(Ti_6O_(11)),W_2C,W_1C화미정명탄화오.기중,TiO_2립경18.8~95.6nm,W_2C립경17.4~24.2 nm,W_1C립경14.7~15.8 nm.재삼전겁체계중,채용순배복안법측정료양품대대초기분분적전최화활성.결과표명,양품적전최화활성여정상조성유관,차W_1C여TiO_2구성복합재료후,량자지간존재명현적협동효응.저설명TiO_2시W_1C적량호재체.
A tungsten carbide-titania nanocomposite was fabricated by combining mechanochemical approach with reduction-carbonization technology using titania nanopowder as the support and using ammonium metatungstate as the tungsten precursor. The crystal phase, the diameter of crystallite, and the morphology of the sample were characterized by X-ray diffraction and scanning electron microscopy. The results showed that the morphology of the sample particles was of irregular granules with same congregations. The crystal phase of the sample was composed of rutile (TiO_2), nonstoichiometric ratio titania (Ti_6O_(11)), bitungsten carbide (W_2C), monotungsten carbide (W_1C), and unnamed tungsten carbide. The diameter of TiO_2 crystallites was 18.8-95.6 nm, that of W_2C was 17.4-24.2 nm, and that of W_1C was 14.7-15.8 nm. The electrocatalytic activity of the sample for p-nitrophenol was measured by cyclic voltammetry in acidic solution with a three-electrode system. The results indicated that the electrocatalytic activity of the sample was correlated to its crystal phases, and a syner-gistic effect existed between tungsten carbide and titania in the nanocomposite.