溶胶-凝胶法制备电极催化剂用纳米WC及其脱玻璃碳研究  

Synthesis of WC Nanopowders for Electrode Catalyst by Sol-Gel and Decarburization Treatment

作　　者：齐德才 周大利[1] 刘灿[1] 胡驰[2] 

机构地区：[1]四川大学材料科学与工程学院,成都610064 [2]四川建筑职业技术学院材料工程系,德阳618000

出　　处：《材料导报（纳米与新材料专辑）》2013年第1期73-76,共4页

摘　　要：以钨酸钠为钨源,酚醛树脂为碳源,采用溶胶-凝胶法制备WC前驱体,在氩气、氢气混合气氛下高温原位还原碳化制备纳米WC。分别采用浓硝酸和氢气对WC中的残余玻璃碳进行脱碳处理。在含有WC的氯铂酸(H2PtCl6.6H2O)悬浊液中采用甲醛(HCHO)还原法制备纳米WC负载纳米Pt的复合粒子,将其制作成工作电极,在酸性介质中采用循环伏安法测试工作电极的电化学催化活性。结果表明:所制备的前驱体颗粒粒径为10～20nm,分布均匀;经1000℃还原碳化1h可制备粒径为40～100nm的纳米WC;采用H2高温还原处理可有效去除WC中的残余玻璃碳,经脱碳处理的WC与Pt制成的10%Pt/WC(质量分数)工作电极在酸性介质中表现出良好的电化学催化活性。Tungsten carbide precursor xerogel was synthesized by sol-gel method, with sodium tungstate as tungsten source and phenolic resin as carbon source. Nano-tungsten carbide （WC） powders were prepared by reduc- tion and carburization under hydrogen and argon atmospheres. Residual glass carbon in WC was removed by treating with concentrated nitric acid soakage and hydrogen reduction. The working electrode was obtained with Pt/WC com posite catalyst material, which was synthesized by reduction of H2 PtCI6 ~ 6H20 with carbinol （HCHO） as reducing agent in the suspended liquid mixed by H2PtCI6 ~ 6H^O and WC. The electrochemical activity of working electrode was tested by cyclic vohammetry method. The results showed that the particle sizes of precursor were well-distributed among 10--20 nm, WC powders with particle sizes among 40--100nm were prepared by reduction and carburization at 1000 ℃ for 1 h. The residual glass carbon of WC could be removed effectively by hydrogen reduction at a high tempe- rature, and the 10% Pt/WC working electrode treated by WC through this method showed excellent electro-catalytic activity.

关 键 词：溶胶-凝胶法 纳米碳化钨 脱碳处理 电催化活性 

分 类 号：TB383[一般工业技术—材料科学与工程]