Developing low-cost and high-efficient noble-metal-free cocatalysts has been a challenge to achieve economic hydrogen production.In this work,molybdenum oxides(MoO3-x)were in situ loaded on polymer carbon nitride(PCN)...Developing low-cost and high-efficient noble-metal-free cocatalysts has been a challenge to achieve economic hydrogen production.In this work,molybdenum oxides(MoO3-x)were in situ loaded on polymer carbon nitride(PCN)via a simple one-pot impregnation-calcination approach.Different from post-impregnation method,intimate coupling interface between high-dispersed ultra-small MoO3-xnanocrystal and PCN was successfully formed during the in situ growth process.The MoO3-x-PCN-X(X=1,2,3,4)photocatalyst without noble platinum(Pt)finally exhibited enhanced photocatalytic hydrogen performance under visible light irradiation(λ>420 nm),with the highest hydrogen evolution rate of 15.6μmol/h,which was more than 3 times that of bulk PCN.Detailed structure-performance revealed that such improvement in visible-light hydrogen production activity originated from the intimate interfacial interaction between high-dispersed ultra-small MoO3-xnanocrystal and polymer carbon nitride as well as efficient charge carriers transfer brought by Schottky junction formed.展开更多
Conjugated polymer photocatalysts have received extensive attention in the field of photocatalytic hydrogen evolution owing to their tunable molecular structures and electronic properties.Herein,we developed three don...Conjugated polymer photocatalysts have received extensive attention in the field of photocatalytic hydrogen evolution owing to their tunable molecular structures and electronic properties.Herein,we developed three donoracceptor(D-A)type thiophene-containing narrow-band-gap conjugated polymers with pyrene as a donor and different fused-thiophene derivatives as acceptors via direct C-H arylation coupling polymerization.It was found that the band gap of the polymers can be tuned by adjusting the number of the fused-thiophene rings.The visible light absorption range can be extended by increasing the number of the thiophene rings,the planar molecular structure for both donor and acceptor units facilitates the charge transmission along the polymer skeleton,and the D-A type polymer structure promotes the dissociation of photo-induced electrons and holes.As a result,a high photocatalytic hydrogen evolution rate of 33.07 mmol h^(−1)g^(−1) was obtained by PyTP-2 with an optimized molecular structure under visible light irradiation(λ>420 nm)without the aid of Pt co-catalyst.In addition,PyTP-2 also shows a photocatalytic activity for oxygen evolution with an average oxygen evolution rate of 58.37µmol h^(−1)g^(−1).展开更多
基金the National Natural Science Foundation of China(No.21872093)the National Key Research and Development Program of China(No.2018YFB1502001)the Center of Hydrogen Science of Shanghai Jiao Tong University。
文摘Developing low-cost and high-efficient noble-metal-free cocatalysts has been a challenge to achieve economic hydrogen production.In this work,molybdenum oxides(MoO3-x)were in situ loaded on polymer carbon nitride(PCN)via a simple one-pot impregnation-calcination approach.Different from post-impregnation method,intimate coupling interface between high-dispersed ultra-small MoO3-xnanocrystal and PCN was successfully formed during the in situ growth process.The MoO3-x-PCN-X(X=1,2,3,4)photocatalyst without noble platinum(Pt)finally exhibited enhanced photocatalytic hydrogen performance under visible light irradiation(λ>420 nm),with the highest hydrogen evolution rate of 15.6μmol/h,which was more than 3 times that of bulk PCN.Detailed structure-performance revealed that such improvement in visible-light hydrogen production activity originated from the intimate interfacial interaction between high-dispersed ultra-small MoO3-xnanocrystal and polymer carbon nitride as well as efficient charge carriers transfer brought by Schottky junction formed.
基金financially supported by the National Natural Science Foundation of China(21574077 and 21304055)the Fundamental Research Funds for the Central Universities(GK202102005)。
文摘Conjugated polymer photocatalysts have received extensive attention in the field of photocatalytic hydrogen evolution owing to their tunable molecular structures and electronic properties.Herein,we developed three donoracceptor(D-A)type thiophene-containing narrow-band-gap conjugated polymers with pyrene as a donor and different fused-thiophene derivatives as acceptors via direct C-H arylation coupling polymerization.It was found that the band gap of the polymers can be tuned by adjusting the number of the fused-thiophene rings.The visible light absorption range can be extended by increasing the number of the thiophene rings,the planar molecular structure for both donor and acceptor units facilitates the charge transmission along the polymer skeleton,and the D-A type polymer structure promotes the dissociation of photo-induced electrons and holes.As a result,a high photocatalytic hydrogen evolution rate of 33.07 mmol h^(−1)g^(−1) was obtained by PyTP-2 with an optimized molecular structure under visible light irradiation(λ>420 nm)without the aid of Pt co-catalyst.In addition,PyTP-2 also shows a photocatalytic activity for oxygen evolution with an average oxygen evolution rate of 58.37µmol h^(−1)g^(−1).
