Search

Predicting and designing highly gas‐sensitive semiconductors is crucial for solving growing environmental problems. Herein, four lateral heterostructures (LHSs), As6/Sb6 AC‐/ZZ‐LHSs and Sb6/Bi6 AC‐/ZZ‐LHSs, are constructed. The adsorption of NO molecule on these LHSs is investigated using first‐principle calculations. The results indicate that the adsorption of NO molecule on As6/Sb6 LHS with armchair (AC) interface is physisorption, whereas NO molecule is chemically adsorbed on As6/Sb6 LHS with zigzag (ZZ) interface and Sb6/Bi6 AC‐/ZZ‐LHSs, with strong adsorption energy and large charge transfer. All LHSs act as charge donors for the NO molecule. Meanwhile, the adsorption of NO molecule causes a significant change in the electronic properties of As6/Sb6 ZZ‐LHS and Sb6/Bi6 AC‐/ZZ‐LHSs, which shows that these LHSs have great potential for application in NO gas sensors. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculation was used to study the potential applications of pure and metal-doped C 24 N 24 fullerene as highly sensitive and selective gas sensors. It is found that gases commonly existing in the air, including NO 2 , CO, NO, NH 3 , N 2 and CO 2 , are weakly adsorbed on pure C 24 N 24. The adsorption strength is increased when they are adsorbed on the metal-doped (Co-, Cr-, Cu-, K-, Li-, Fe-, Ni-, Pd-, Ti-, Mn-, Na-, Zn-, V-) C 24 N 24. The pure and metal-doped C 24 N 24 have a specific response to certain gas according to adsorption energy, charge transfer, band gap and the density of states analyses. Among various metal-doped C 24 N 24 , the adsorption energies of NO 2 on K- and Na-doped C 24 N 24 are apparently lager than those of other gas molecules, which fall between the suitable range of strong physical adsorption and weak chemical adsorption. Upon NO 2 adsorption, the band gap changes of K- and Na-doped C 24 N 24 which corelate with its conductivity reach −12.75% and −26.67%, respectively. In accordance with the band gap changes, the density of states changes and charge transfer for NO 2 adsorption on K- and Na-doped C 24 N 24 are most obvious. Sensor performance analysis further shows K- and Na-doped C 24 N 24 are highly selective in NO 2 detection. The recycle time of Na–C 24 N 24 under ambient condition is also in the suitable range (1.80 s). This study concludes the potential application of the Na-doped C 24 N 24 as high-performance NO 2 sensor. [ABSTRACT FROM AUTHOR]