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.
引文
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