Synthesis and in-situ noble metal modification of WO3·0.33H2O nanorods from a tungsten-containing mineral for enhancing NH3 sensing performance

查看全文 作　　者：Tingting [1]Li;Yanbai [1,3]Shen;Sikai [1]Zhao;Pengfei [1]Zhou;Xiangxi [1]Zhong;Shuling [1]Gao;Dezhou [1]Wei;Fanli [2]Meng 机构地区：[1]School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China;[2]School of Information Science and Engineering,Northeastern University,Shenyang 110819,China;[3]State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control,Wuhan University of Science and Technology,Wuhan 430081,China 出　　处：《Chinese Chemical Letters》索引2020年第31卷第8期,共4页 基　　金：supported by the National Natural Science Foundation of China(Nos.51674067,51422402);FundamentalResearch Funds for the Central Universities(Nos.N180102032,N180106002,N180408018,N170106005);Liaoning Revitalization Talents Program(No.XLYC1807160);Liaoning BaiQianWan Talents Program(No.201892127);Open Foundation of State Key Laborato ry of Mineral Processing(No.BGRIMM-KJSKL-2019-12);Open Foundation of State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control(No.HB201902)。 摘　　要：Ag-and Pt-doped WO3-0.33 H2O nanorods with high response and selectivity to NH3 were synthesized from a tungsten-containing mine ral of scheelite concentrate by a simple combined process,namely by a high pressure leaching method to obtain tungstate ions-containing leaching solution and followed by a hydrothermal method to prepare corresponding nanorods.The microstructure and NH3 sensing perfo rmance of the final products were investigated systematically.The microstructure characte rization showed that the as-prepared WO3-0.33 H2 O nanorods had a hexagonal crystal structure,and Ag and Pt nanoparticles were uniformly distributed in the WO3-0.33 H2O nano rods.Gas sensing measurements indicated that Ag and Pt nanopa rticles not only could obviously enhance NH3 sensing properties in terms of response,selectivity as well as response/recovery time,but also could reduce the optimal operating temperature at which the highest response was achieved.The highest responses of 22.4 and 47.6 for Agand Pt-doped WO3-0.33 H2O nanorods to 1000 ppm NH3 were obtained at 225 and 175℃,respectively,which were about four and eight folds higher than that of pure one at 250℃.The superior NH3 sensing properties are mainly ascribed to the catalytic activities of noble metals and the different work functions between noble metals and WO3-0.33 H2 O. 关 键 词：Scheelite concentrate Noble metal doping WO3·0.33H2O nanorods NH3 Sensing mechanism