薄层氮化碳光催化还原CO_2性能研究
|
摘要
以氮化碳(g-CN)为原料,采用水蒸汽焙烧剥离法在Ar/H2O氛围下制备薄层氮化碳(Hg-CN),并对其进行XRD、TEM、FT-IR、BET和UV-Vis DRS等表征。结果表明,进行剥离后,H-g-CN比表面积相比剥离前明显增大。H-g-CN的光催化还原CO_2活性大大高于未剥离gCN的活性,光照反应9 h,H-g-CN光催化还原CO_2活性由剥离前的11. 4μmol·g~(-1)提高至24. 6μmol·g~(-1),H-g-CN的CO选择性为91. 2%,未剥离的g-CN的CO选择性为89. 1%,并提出相应的反应机理。
The thin-layered carbon nitrides( H-g-CN) were successfully synthesized by calcination of carbon nitride( g-CN) in Ar/H2 O atmosphere,and they were characterized by means of XRD,TEM,FT-IR,BET and UV-Vis DRS. It was found that,compared with g-CN,the specific surface area of H-g-CN obviously increased after calcination. The activity for CO_2 photoreduction of H-g-CN was much higher than that of g-CN. After 9 h light irradiation,the photocatalytic reduction of CO_2 activity of thin-layered carbon nitride( g-CN) was promoted to 24. 6 μmol·g~(-1) from 11. 4 μmol·g~(-1) of carbon nitride( g-CN),in that case,the CO selectivity of H-g-CN was 91. 2%,and the CO selectivity of carbon nitride before calcination was 89. 1%. Moreover,the reaction mechanism was proposed.
The thin-layered carbon nitrides( H-g-CN) were successfully synthesized by calcination of carbon nitride( g-CN) in Ar/H2 O atmosphere,and they were characterized by means of XRD,TEM,FT-IR,BET and UV-Vis DRS. It was found that,compared with g-CN,the specific surface area of H-g-CN obviously increased after calcination. The activity for CO_2 photoreduction of H-g-CN was much higher than that of g-CN. After 9 h light irradiation,the photocatalytic reduction of CO_2 activity of thin-layered carbon nitride( g-CN) was promoted to 24. 6 μmol·g~(-1) from 11. 4 μmol·g~(-1) of carbon nitride( g-CN),in that case,the CO selectivity of H-g-CN was 91. 2%,and the CO selectivity of carbon nitride before calcination was 89. 1%. Moreover,the reaction mechanism was proposed.
引文
[1]Xiao J,Xie Y,Cao H,et al. g-C3N4-triggered super synergy between photocatalysis and ozonation attributed to promoted,OH generation[J]. Catalysis Communications,2015,66:10-14.
[2]Liao G,Zhu D,Li L,et al. Enhanced photocatalyticozonation of organics by g-C3N4under visible light irradiation[J].Journal of Hazardous Materials,2014,280:531-535.
[3]Chen W,Liu T,Huang T,et al. Novel yet simple strategy to fabricate visible light responsive C,N-Ti O2/g-C3N4heterostructures with significantly enhanced photocatalytic hydrogen generation[J]. Rsc Advances,2015,(5):101214-101220.
[4]Zhang L,Jing D,She X,et al. Heterojunctions in g-C3N4/Ti O2(B)nanofibres with exposed(001)plane and enhanced visible-light photoactivity[J]. Journal of Materials Chemistry A,2014,(2):2071-2078.
[5]Li K,Peng B,Jin J,et al. Carbon nitride nanodots decorated brookite Ti O2,quasi nanocubes for enhanced activity and selectivity of visible-light-driven CO2,reduction[J].Applied Catalysis B Environmental,2017,203:910-916.
[6]She X,Wu J,Zhong J,et al. Oxygenated monolayer carbon nitride for excellent photocatalytic hydrogen evolution and external quantum efficiency[J]. Nano Energy,2016,27:138-146.
[7]Lu X,Xu K,Chen P,et al. Facile one step method realizing scalable production of g-C3N4nanosheets and study of their photocatalytic H2evolution activity[J]. Journal of Materials Chemistry A,2014,2:18924-18928.
[8]Yang P,Ou H,Fang Y,et al. A facile steam reforming strategy to delaminate layered carbon nitride semiconductors for photoredox catalysis[J]. Angewandte Chemie,2017,56:3992-3996.
[9]Yang S,Gong Y,Zhang J,et al. Exfoliated graphitic carbon nitride nanosheets as efficient catalysts for hydrogen evolution under visible light[J]. Advanced Materials,2013,25:2452-2456.
[10]Zhu Y P,Li M,Liu Y L,et al. Carbon-doped Zn O hybridized homogeneously with graphitic carbon nitride nanocomposites for photocatalysis[J]. Journal of Physical Chemistry C,2014,118:10963-10971.
[11]Zhu J,Diao T,Wang W,et al. Boron doped graphitic carbon nitride with acid-base duality for cycloaddition of carbon dioxide to epoxide under solvent-free condition[J].Applied Catalysis B Environmental,2017,219:92-100.
[2]Liao G,Zhu D,Li L,et al. Enhanced photocatalyticozonation of organics by g-C3N4under visible light irradiation[J].Journal of Hazardous Materials,2014,280:531-535.
[3]Chen W,Liu T,Huang T,et al. Novel yet simple strategy to fabricate visible light responsive C,N-Ti O2/g-C3N4heterostructures with significantly enhanced photocatalytic hydrogen generation[J]. Rsc Advances,2015,(5):101214-101220.
[4]Zhang L,Jing D,She X,et al. Heterojunctions in g-C3N4/Ti O2(B)nanofibres with exposed(001)plane and enhanced visible-light photoactivity[J]. Journal of Materials Chemistry A,2014,(2):2071-2078.
[5]Li K,Peng B,Jin J,et al. Carbon nitride nanodots decorated brookite Ti O2,quasi nanocubes for enhanced activity and selectivity of visible-light-driven CO2,reduction[J].Applied Catalysis B Environmental,2017,203:910-916.
[6]She X,Wu J,Zhong J,et al. Oxygenated monolayer carbon nitride for excellent photocatalytic hydrogen evolution and external quantum efficiency[J]. Nano Energy,2016,27:138-146.
[7]Lu X,Xu K,Chen P,et al. Facile one step method realizing scalable production of g-C3N4nanosheets and study of their photocatalytic H2evolution activity[J]. Journal of Materials Chemistry A,2014,2:18924-18928.
[8]Yang P,Ou H,Fang Y,et al. A facile steam reforming strategy to delaminate layered carbon nitride semiconductors for photoredox catalysis[J]. Angewandte Chemie,2017,56:3992-3996.
[9]Yang S,Gong Y,Zhang J,et al. Exfoliated graphitic carbon nitride nanosheets as efficient catalysts for hydrogen evolution under visible light[J]. Advanced Materials,2013,25:2452-2456.
[10]Zhu Y P,Li M,Liu Y L,et al. Carbon-doped Zn O hybridized homogeneously with graphitic carbon nitride nanocomposites for photocatalysis[J]. Journal of Physical Chemistry C,2014,118:10963-10971.
[11]Zhu J,Diao T,Wang W,et al. Boron doped graphitic carbon nitride with acid-base duality for cycloaddition of carbon dioxide to epoxide under solvent-free condition[J].Applied Catalysis B Environmental,2017,219:92-100.