Pt/ZnSnO3纳米片复合物制备及气敏性研究

摘要

采用水热、回流还原法先分别制得ZnSnO3纳米片及单分散Pt纳米晶稳定溶胶,然后利用化学自组装法将贵金属Pt纳米晶镶嵌到ZnSnO3纳米片上.利用XRD、SEM、TEM等分别对Pt/ZnSnO3纳米片复合物结构、微观形貌等进行表征,结果表明:通过化学自组装法Pt纳米晶成功修饰到ZnSnO3纳米片上,且分布相对均匀.采用传统旁热式结构对不同Pt含量的Pt/ZnSnO3纳米片复合物进行气敏性研究,结果发现Pt含量0.4％的Pt/ZnSnO3纳米片复合物气敏性能最佳:工作温度300℃时,对0.1 ppm乙醇及0.3 ppm甲醛有较好的响应;乙醇、甲醛气体浓度为10 ppm时,灵敏度分别达50.9和15.3.相对纯ZnSnO3纳米片而言,其检测下限、灵敏度、选择性等都得到很大的改善.%ZnSnO3 nanosheets and monodisperse Pt nanocrystals sol were first synthesized by hydrothermal method and reflux reduction method respectively, and then the precious metal Pt nanocrystals were assembled on ZnSnO3 nanosheets by a chemical self-assembly method. X-ray diffraction, scanning electron microscopy and high resolution transmission electron microscopy have been employed to characterize the crystal structure and morphology of the as-synthesized Pt/ZnSnO3nanosheets composites. The results show that Pt nanocrystals were successfully loaded on ZnSnO3 nanosheets by chemical self-assembly method, and also achieved relatively uniform distribution. Through the controlled addition of monodisperse Pt nanocrystals sol, different distribution density of Pt nanocrystals on Pt/ZnSnO3 nanosheets can also be obtained. The as-fabricated Pt/ZnSnO3 nanosheets-based sensor composites with different Pt content were tested. Results showed that the nano Pt/ZnSnO3 composite with 0.4％ of Pt has the best sensing properties at the optimal working temperature of 300 ℃, and has good response to 0.1 ppm ethanol and 0.3 ppm formaldehyde. When the concentration of ethanol and formaldehyde is 10 ppm, it sensitivity was 50.9 and 15.3 respectively. The detection limit, sensitivity, selectivity and so on are improved greatly compared with those of pure ZnSnO3 nanosheets.