The limited CO_(2)content in aqueous solution and low adsorption amount of CO_(2)on catalyst surface lead to poor photocatalytic CO_(2)reduction activity and selectivity.Herein,the design and fabrication of a novel ph...The limited CO_(2)content in aqueous solution and low adsorption amount of CO_(2)on catalyst surface lead to poor photocatalytic CO_(2)reduction activity and selectivity.Herein,the design and fabrication of a novel photocatalytic architecture is reported,accomplished via chemical vapor deposition of polymeric carbon nitride on carbon paper.The as-obtained samples with a hydrophobic surface exhibit excellent CO_(2)transport and adsorption ability,as well as the building of triphase air-liquid-solid(CO_(2)-H_(2)O-catalyst)joint interfaces,eventually resulting in the inhibition of H2 evolution and great promotion of CO_(2)reduction with a selectivity of 78.6%.The addition of phosphate to reaction environment makes further improvement of CO_(2)photoreduction into carbon fuels with a selectivity of 93.8%and an apparent quantum yield of 0.4%.This work provides new insight for constructing efficient photocatalytic architecture of CO_(2)photoreduction in aqueous solution and demonstrates that phosphate could play a key role in this process.展开更多
The title compound 2,5-bis(morpholino)-3,4-bis(p-chlorophenyl) thiophene 2 was obtained by the reaction of -thio-p-chlorobenzoyl thioformmorpholine 1 with trimethyl phosphite in refluxing xylene. The crystal is of tri...The title compound 2,5-bis(morpholino)-3,4-bis(p-chlorophenyl) thiophene 2 was obtained by the reaction of -thio-p-chlorobenzoyl thioformmorpholine 1 with trimethyl phosphite in refluxing xylene. The crystal is of triclinic, space group P?with unit cell constants: a = 6.0740(1), b = 10.3250(1), c = 19.779(2) , ?= 76.740(1), = 87.110(1), = 74.920(1), C24H24Cl2N2O2S, Mr = 475.41, Z = 2, V = 1165.7(3) ?, Dc = 1.354 g/cm3, (MoK) = 0.71073, = 0.392 mm-1, F(000) = 496, the final R = 0.0324 and wR = 0.0819 for 3102 observed reflections (I > 2(I)). X-ray analysis reveals that the two morpholinyl groups are located at the -position of thiophene, and the two p-chlorophenyl groups at the -position. Therefore, the title compound is a new symmetric thiophene derivative.展开更多
The catalytic activity of trimethyl phosphite modified HZSM-5 zeolite and un-modified HZSM-5zeolite treated with 100% steam at 673,773,873,973 and 1073K, respectively, were investigated using heptanecracking as a prob...The catalytic activity of trimethyl phosphite modified HZSM-5 zeolite and un-modified HZSM-5zeolite treated with 100% steam at 673,773,873,973 and 1073K, respectively, were investigated using heptanecracking as a probe reaction. The results showed that the heptane conversion of both trimethyl phosphitetreated samples and un-phosphated samples decreased with an increase in treating temperature, but trimethylphosphite modified samples showed higher activity in comparison with the un-modified samples, which weresteam-treated at a higher temperature. The results were firstly elucidated by the model cluster method andcomputational quantum chemistry method. Full optimization and frequency analysis of all cluster model havebeen carried out using the Gaussian 94 software-package with the PM 3 semi-empirical method performed onsmall cluster models. The computational results showed that the dealumination of trimethyl phosphite modi-fied zeolite model cluster was more difficult than that of un-modified zeolite model cluster when they weretreated with steam while investigating the heat of reaction.展开更多
文摘The limited CO_(2)content in aqueous solution and low adsorption amount of CO_(2)on catalyst surface lead to poor photocatalytic CO_(2)reduction activity and selectivity.Herein,the design and fabrication of a novel photocatalytic architecture is reported,accomplished via chemical vapor deposition of polymeric carbon nitride on carbon paper.The as-obtained samples with a hydrophobic surface exhibit excellent CO_(2)transport and adsorption ability,as well as the building of triphase air-liquid-solid(CO_(2)-H_(2)O-catalyst)joint interfaces,eventually resulting in the inhibition of H2 evolution and great promotion of CO_(2)reduction with a selectivity of 78.6%.The addition of phosphate to reaction environment makes further improvement of CO_(2)photoreduction into carbon fuels with a selectivity of 93.8%and an apparent quantum yield of 0.4%.This work provides new insight for constructing efficient photocatalytic architecture of CO_(2)photoreduction in aqueous solution and demonstrates that phosphate could play a key role in this process.
基金The project was supported by the Natural Science Foundation of Jiangsu Education Committee (99KJB 150001)
文摘The title compound 2,5-bis(morpholino)-3,4-bis(p-chlorophenyl) thiophene 2 was obtained by the reaction of -thio-p-chlorobenzoyl thioformmorpholine 1 with trimethyl phosphite in refluxing xylene. The crystal is of triclinic, space group P?with unit cell constants: a = 6.0740(1), b = 10.3250(1), c = 19.779(2) , ?= 76.740(1), = 87.110(1), = 74.920(1), C24H24Cl2N2O2S, Mr = 475.41, Z = 2, V = 1165.7(3) ?, Dc = 1.354 g/cm3, (MoK) = 0.71073, = 0.392 mm-1, F(000) = 496, the final R = 0.0324 and wR = 0.0819 for 3102 observed reflections (I > 2(I)). X-ray analysis reveals that the two morpholinyl groups are located at the -position of thiophene, and the two p-chlorophenyl groups at the -position. Therefore, the title compound is a new symmetric thiophene derivative.
文摘The catalytic activity of trimethyl phosphite modified HZSM-5 zeolite and un-modified HZSM-5zeolite treated with 100% steam at 673,773,873,973 and 1073K, respectively, were investigated using heptanecracking as a probe reaction. The results showed that the heptane conversion of both trimethyl phosphitetreated samples and un-phosphated samples decreased with an increase in treating temperature, but trimethylphosphite modified samples showed higher activity in comparison with the un-modified samples, which weresteam-treated at a higher temperature. The results were firstly elucidated by the model cluster method andcomputational quantum chemistry method. Full optimization and frequency analysis of all cluster model havebeen carried out using the Gaussian 94 software-package with the PM 3 semi-empirical method performed onsmall cluster models. The computational results showed that the dealumination of trimethyl phosphite modi-fied zeolite model cluster was more difficult than that of un-modified zeolite model cluster when they weretreated with steam while investigating the heat of reaction.
