六方相氧化钨纳米线的制备及氨敏特性

采用简易水热法制备直径为10～20 nm、长几百纳米至几微米的六方相氧化钨纳米线,比表面积高达130.69 m~2/g.将该纳米线采用丝网印刷法制备成敏感膜,经350 ℃烧结1 h后测试其氨敏性能并分析其敏感机制.结果表明:在200～350 ℃的温度范围内,该敏感膜对低浓度氨气(1～100) μL/L具有较高的灵敏度(R_(air)/R_(NH_3)=4.0～18.8)、良好的重复性和很好的稳定性;对同一浓度的氨气,随测试温度的升高其灵敏度不断增大;在同一温度下,灵敏度随氨气浓度的增加基本上呈线性不断增大.

Preparation of Hexagonal WO_3 Nanowires and NH_3 Sensing Characteristics

Hexagonal tungsten oxide nanowires were prepared by a simple hydrothermal method. The diameter of the nanowires is about 10～20 nm, the length is up to several micrometers and the specific area is 130.69 m~2/g. Thick film gas sensor was prepared by screen-printing technology and sintered at 350 ℃ for 1 h. The NH3 sensing properties and sensing mechanics at low concentrations (1-100 μL/L) were investigated in the temperature range from 200 to 350 ℃. It shows a high sensitivities (R_a/R_g) (4.0-18.8), good repeatability and stability. The sensitivity increased with increasing the operating temperature from 200 ℃ to 350 ℃ for the same NH_3 concentration. At the same temperature, the sensitivity increased almost linearly with increasing the concentration of NH_3 gas from 1-100 μL/L.