Li Yunfeng, Yang Man, Xing Yan, Liu Xianchun, Yang Yang, Wang Xiao, Song Shuyan
Jilin Provincial Key Laboratory of Advanced Energy Materials, Department of Chemistry, Northeast Normal University, Changchun, 130024, P. R. China.
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China.
Small. 2017 Sep;13(33). doi: 10.1002/smll.201701552. Epub 2017 Jul 10.
Exfoliation of layered bulk g-C N (CNB) to thin g-C N sheets in nanodomains has attracted much attention in photocatalysis because of the intriguing properties of nanoscaled g-C N . This study shows that carbon-rich g-C N nanosheets (CNSC) can be easily prepared by self-modification of polymeric melon units through successively thermally treating bulk g-C N in an air and N atmosphere. The prepared CNSC not only retain the outstanding properties of nanosheets, such as large surface area, high aspect ratios, and short charges diffusion distance, but also overcome the drawback of enlarged bandgap caused by the quantum size effect, resulting in an enhanced utilization of visible light and photoinduced electron delocalization ability. Therefore, the as-prepared CNSC show a high hydrogen evolution rate of 39.6 µmol h with a turnover number of 24.98 in 1 h at λ > 400 nm. Under irradiation by longer wavelength of light (λ > 420 nm), CNSC still exhibit a superior hydrogen evolution rate, which is 72.9 and 5.4 times higher than that of bulk g-C N and g-C N nanosheets, respectively.
在光催化领域，将层状块状石墨相氮化碳（CNB）剥离成纳米域中的薄石墨相氮化碳片层因其纳米级石墨相氮化碳的有趣特性而备受关注。本研究表明，通过在空气和氮气气氛中对块状石墨相氮化碳进行连续热处理，聚合物类石墨氮（melon）单元的自改性可轻松制备富碳石墨相氮化碳纳米片（CNSC）。所制备的CNSC不仅保留了纳米片的优异特性，如大表面积、高纵横比和短电荷扩散距离，还克服了量子尺寸效应导致的带隙增大的缺点，从而提高了可见光的利用率和光致电子离域能力。因此，所制备的CNSC在λ>400nm时表现出39.6μmol h的高析氢速率，1小时内的周转数为24.98。在较长波长光（λ>420nm）照射下，CNSC仍表现出优异的析氢速率，分别是块状石墨相氮化碳和石墨相氮化碳纳米片的72.9倍和5.4倍。
