p-CuO/n-ZnO Heterojunction Structure for the Selective Detection of Hydrogen Sulphide and Sulphur Dioxide Gases: A Theoretical Approach

Abstract

DFT calculations at the B3LYP/LanL2DZ level of theory were utilized to investigate the adsorption of H2S and SO2 gases on the electronic properties of CuO-ZnO heterojunction structures. The results were demonstrated from the standpoint of adsorption energies (Eads), the density of states (DOS), and NBO atomic charges. The obtained values of the adsorption energies indicated the chemisorption of the investigated gases on CuO-ZnO heterojunction. The adsorption of H2S and SO2 gases reduced the HOMO-LUMO gap in the Cu2Zn10O12 cluster by 4.98% and 43.02%, respectively. This reveals that the Cu2Zn10O12 cluster is more sensitive to the H2S gas than the SO2 gas. The Eads values for SO2 and H2S were −2.64 and −1.58 eV, respectively. Therefore, the Cu2Zn10O12 cluster exhibits a higher and faster response-recovery time to H2S than SO2. Accordingly, our results revealed that CuO-ZnO heterojunction structures are promising candidates for H2S- and SO2-sensing applications.

Mg12O12 and Be12O12 Nanocages as Sorbents and Sensors for H2S and SO2 Gases: A Theoretical Approach

“…Furthermore, SO 2 causes skin burning, eye irritation and respiratory system inflammation, and may cause death [ 7 , 13 , 14 , 15 ]. Therefore, several attempts have been made to utilize many materials as sorbents and detectors for H 2 S and SO 2 gases, such as fullerene-like gallium nitride [ 16 ], CuO(111) surface [ 17 ], pristine graphene and graphene oxide [ 18 ], NH-decorated graphene [ 8 ], activated carbon, [ 19 , 20 ], pillared clays [ 21 ], zeolites [ 22 ], p-CuO/n-ZnO Heterojunction [ 23 ], Cu (100) and Au (100) surfaces [ 24 , 25 ], Cu doped MoSe 2 [ 12 ], monolayer Janus MoSSe [ 26 ], aza-macrocycle [ 27 ], Cu-modified and Cu-embedded WSe 2 monolayers [ 28 ], porous N 4 O 4 -donor macrocyclic Schiff base [ 29 ] and MgO (100) surfaces [ 10 ].…”