一种高抗湿的二氧化锡室温氢敏陶瓷的制备与研究

Preparation and characterization of a room-temperature hydrogen sensitive Pt-SnO_2 composite nanoceramics with high humidity tolerance

湿度的影响是金属氧化物半导体室温气敏材料应用中面临的主要挑战之一。本文通过传统的陶瓷制备工艺,将二氧化锡纳米粉与铂粉混合制备成块状的纳米复合陶瓷。这种块体陶瓷材料在室温50%相对湿度环境下对于较高浓度的氢气具有显著的响应,其对于体积分数1%的氢气响应很好,灵敏度可以达到150。然而它在50%相对湿度的环境下对低浓度氢气的响应仍然会受到很大的抑制。另外,二氧化锡团聚体颗粒也被作为原料用来制备Pt-SnO_2复合纳米陶瓷。在室温以及50%相对湿度环境下,它对体积分数1%的氢气灵敏度高达850,而当相对湿度上升到70%的时候,灵敏度依然能达到450。对于很低浓度的氢气,它也保留着显著的氢敏性能,在50%和70%的相对湿度下,对体积分数为0.04%的氢气灵敏度分别为5和4.1。显然,这种块体陶瓷材料在具备更强的抗湿性能的同时具有更高的灵敏度。微观结构显示这种块体陶瓷材料存在许多团聚体,这种不均匀的微观结构对于抗湿性能的调控具有非常重要的意义。

The influence of humidity is one of the major challenges for the application of room-temperature hydrogen materials based on semiconducting metal oxides. Pt-SnO 2 nanocomposite ceramics were prepared with SnO 2 nanoparticles and Pt powder using traditional ceramic preparation method. This ceramic materials show a sensitivity up to 150 at 1% H 2 in air under 50% relative humidity (RH) at room temperature. However, its response to low concentration of hydrogen (≤0. 1%) at moderate humidity (50% RH) is largely suppressed. SnO 2 agglomerate powder is also used as raw material to prepare Pt-SnO 2 nanocompositeceramics, which surprisingly show much higher sensitivities of 850 and 450 under 50% and 70% RH respectively at 1% H 2 in air. For low hydrogen concentration (≤0. 1%), it also maintains remarkable hydrogen sensing capabilities. At 50% and 70% RH, the sensitivity to 0. 04% H 2 in air is 5 and 4. 1 respectively. Obviously, these materials have high humidity tolerance and improved sensing capabilities. Microstructure analysis show that there are many agglomerates in the ceramics, the non-uniform microstructures play an important role in moisture resistance.