【摘要】 采用一步溶液法制备"三明治"PbS纳米晶/rGO复合材料,通过X射线衍射仪和场发射扫描电子显微镜对样品的晶体结构和表面形貌进行表征,并制作旁热式气敏元器件,测试其气敏特性。研究结果表明在PbS纳米晶/rGO复合材料中,PbS纳米晶均匀负载在rGO片层上,且复合材料存在类似"三明治"的三维结构。该复合材料在室温下对NH₃具有良好检测能力,对1000 ppm NH₃的灵敏度达到3.45,与纯PbS纳米晶及rGO相比,气敏性能得到显著提升,其最低检测极限为1 ppm,且具有良好的氨气选择性。对"三明治"PbS纳米晶/rGO复合材料气敏机理进行分析认为,rGO加入起到载流子传输层的作用,三维结构增加气体扩散速度及吸附面积。三明治状PbS纳米晶/rGO复合材料因其特殊结构及优异的气敏性能,有望在气敏领域得到广泛应用。更多还原

【Abstract】 Sandwich-like PbS nanocrystals（ NCs）/rGO composites were prepared by one-step solution method. The crystal structure and surface morphology of the samples were characterized by X-ray diffraction and Field emission scanning electron microscopy. The gas sensor was fabricated with external heating to test its gas properties. The results show that PbS NCs are decorated uniformly on the rGO sheet with a 3-D sandwich-like structure in the composites. The composite has good gas sensing properties to NH₃ at room temperature. PbS NCs/rGO composites possess a quite good gas response towards ammonia gas,the response of 1000 ppm NH₃ is 3. 45,which is obviously enhanced compared with pure PbS NCs and rGO. The composite has the detection limit of 1 ppm to NH₃ gas with a good selectivity. The gas sensing mechanism shows the rGO in the composite acts as a carrier transport layer while the 3-D structure increases the gas diffusion rate and adsorption area. The composite is expected to be widely used in NH₃ detection at room temperature due to its special structure and excellent gas sensing performance.更多还原