Preparation of CeO2-In2O3 heterojunction composites for gas sensing monitoring of triethylamine
CeO2-In2O3 composites were synthesized by pyrolysis metal-organic framework method(MOFs)using In(NO3)3∙4.5H2O and Ce(NO3)3∙6H2O as raw materials,terephthalic acid as ligand and N,N-dimethylformamide as organic solvent.The microstructure of the obtained materials was characterized by XRD,TEM,SEM,UV-vis and BET.The gas sensitive properties of obtained CeO2-In2O3 composites were studied.The results indicated that when the molar ratio of In/Ce was 3∶1,CeO2-In2O3 to 1×105μg/L triethylamine(TEA)had the highest response values(48.37),which was 5 times that of pure In2O3(9.45),response/recovery time was reduced to 36s/22s,and the composite had excellent selectivity and long-term stability at the optimum operating temperature of 173℃.The increased sensing performance can be attributed to the large specific surface area provided by pyrolytic metal-organic skeleton method and the formation of n-n heterojunction.