Metal organic framework-derived Ni4Mo/MoO2@C composite nanospheres as the sensing materials for hydrogen sulfide detection

Abstract

Hydrogen sulfide is carcinogenic, corrosive, and flammable, and pathological for most physiological processes. Nevertheless, precise and efficient H2S detection remains challenging. Metal organic framework (MOF) derived metal alloy/oxide nanostructures have been developed recently that show enormous potential and outstanding performance for accurate H2S detection. This paper proposes a new category of MOF derived metal alloy/oxide nanostructures prepared by wet chemical synthesis as plausible H2S gas sensing materials. Compared with pristine sensors, NiMo-MOF sensors exhibit improved H2S gas sensing performance attributed to synergistic effects and large surface areas. NiMo-MOF sensing material achieves the best known gas response for H2S with negligible response to other gas molecules, including HCHO, SO2, C2H5OH, CH3OH, and NH3. Hydrogen sulfide gas response for NiMo-MOF is 3.5 and 2.6 fold higher than bare Ni-MOF and Mo-MOF respectively. The real-time gas response shows that constructed H2S sensor follows an adsorption-oxidation-desorption mechanism and achieved Rg/Ra value is 126 for NiMo-MOF. Thus, the proposed approach provides a mechanism to employ MOF-derived metal alloy/oxide nanostructures as active candidates for improved gas sensing towards effective H2S detection.