Adsorption behaviors of 2-bromothiophene on the Rh(111) surface were discussed with DFT. The results revealed that adsorption at the parallel hol site and bridge site was the most stable. After adsorption, bond leng...Adsorption behaviors of 2-bromothiophene on the Rh(111) surface were discussed with DFT. The results revealed that adsorption at the parallel hol site and bridge site was the most stable. After adsorption, bond length of 2-bromothiophene changed significantly. Molecular plane was distorted, and C-H (Br, S) in the molecule was oblique and upswept against the metal surface. Vertical adsorption site was less stable than the plane adsorption site, but there was no distortion for the thiophene ring after adsorption. Aromaticity of 2-bromothiophene was destroyed at the hol and bridge adsorption sites, and the carbon atom in the thiophene ring presented quasi-sp3 hybfidizaton. After adsorption at the parallel hol, 2-bromothiophene obtained 0.86 electrons in total, and Rh(111) surface lost 2.08 electrons in all.展开更多
Defect engineering has being regarded as one of the effective ways to regulate chemical and electronic structure of semiconductors.Recently,our collaborative work has shown experimentally that carbon vacancy on polyme...Defect engineering has being regarded as one of the effective ways to regulate chemical and electronic structure of semiconductors.Recently,our collaborative work has shown experimentally that carbon vacancy on polymeric carbon nitride(CV)can greatly improve the CO2 to CO conversion with a 45-fold improvement over the polymeric carbon nitride(Angew.Chem.Int.Ed.,2019,58,1134).In order to clarify the detailed mechanism of promotion,we have systematically studied the electronic properties of CV and hydrogenated CV(CV+H)as well as the effective CO2 reduction reaction through density functional theory calculations.We found that it is the synergistic effect for the CO2 reduction reaction in the CV systems,as the onset potentials of several CVs are much lower than that of the polymeric carbon nitride.In particular,the onset potentials of CV1,CV2,and CV2+H are around 0.9~1.5 eV with a strong chemisorbed CO2 on them.Combined with the analysis of the electronic properties,our results confirm that defect engineering increases the lifetime of photo-generated charges,improves photocatalytic activity,and promotes the CO2 reduction reaction on the defected polymeric carbon nitrides.展开更多
基金Supported by the National Natural Science Foundation of China(No.20273013)the Natural Science Foundation of Fujian Province(No.2002F010)the State Key Laboratory of Structural Chemistry(20090060)
文摘Adsorption behaviors of 2-bromothiophene on the Rh(111) surface were discussed with DFT. The results revealed that adsorption at the parallel hol site and bridge site was the most stable. After adsorption, bond length of 2-bromothiophene changed significantly. Molecular plane was distorted, and C-H (Br, S) in the molecule was oblique and upswept against the metal surface. Vertical adsorption site was less stable than the plane adsorption site, but there was no distortion for the thiophene ring after adsorption. Aromaticity of 2-bromothiophene was destroyed at the hol and bridge adsorption sites, and the carbon atom in the thiophene ring presented quasi-sp3 hybfidizaton. After adsorption at the parallel hol, 2-bromothiophene obtained 0.86 electrons in total, and Rh(111) surface lost 2.08 electrons in all.
基金financially supported by the National Natural Science Foundation of China(21973014,21773030)the Award Program of Minjiang Scholar Professorship for financial support。
文摘Defect engineering has being regarded as one of the effective ways to regulate chemical and electronic structure of semiconductors.Recently,our collaborative work has shown experimentally that carbon vacancy on polymeric carbon nitride(CV)can greatly improve the CO2 to CO conversion with a 45-fold improvement over the polymeric carbon nitride(Angew.Chem.Int.Ed.,2019,58,1134).In order to clarify the detailed mechanism of promotion,we have systematically studied the electronic properties of CV and hydrogenated CV(CV+H)as well as the effective CO2 reduction reaction through density functional theory calculations.We found that it is the synergistic effect for the CO2 reduction reaction in the CV systems,as the onset potentials of several CVs are much lower than that of the polymeric carbon nitride.In particular,the onset potentials of CV1,CV2,and CV2+H are around 0.9~1.5 eV with a strong chemisorbed CO2 on them.Combined with the analysis of the electronic properties,our results confirm that defect engineering increases the lifetime of photo-generated charges,improves photocatalytic activity,and promotes the CO2 reduction reaction on the defected polymeric carbon nitrides.