Zhu Lei, Liu Yi, Peng Xingcui, Li Yibao, Men Yu-Long, Liu Peng, Pan Yun-Xiang
Key Laboratory of Organo-Pharmaceutical Chemistry, Gannan Normal University, Ganzhou 341000, P. R. China.
Department of Instrument Science and Engineering, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
ACS Appl Mater Interfaces. 2020 Mar 18;12(11):12892-12900. doi: 10.1021/acsami.0c00163. Epub 2020 Mar 9.
Graphene oxide (GO) nanosheets are promising noble-metal-free catalysts. However, the catalytic activity and selectivity of GO are still very low. Herein, GO is first functionalized via noncovalent interactions by an aspartic acid modified anhydride having COOH groups to form A-GO. A-GO is more conductive and hydrophilic than GO and P-GO synthesized via functionalizing GO by a COOH-free anhydride. Then, we load CdS nanoparticles, which are responsible for absorbing light to produce charge carriers, on A-GO to fabricate a CdS/A-GO photocatalyst without noble metals for the photoreduction of CO by HO. CdS/A-GO exhibits a higher photoreduction efficiency than that of CdS/GO and CdS/P-GO. The main carbon-based photoreduction product of CdS/A-GO is CHOH, whereas that of CdS/GO and CdS/P-GO is CO. The more conductive and hydrophilic A-GO triggers a more efficient electron transfer, CO adsorption, and production of hydrogen atoms from HO dissociation, thus leading to the higher photoreduction efficiency and product change on CdS/A-GO. Besides, the COOH groups of the aspartic acid modified anhydride supply their hydrogen atoms to promote the conversion from CO to CHOH on CdS/A-GO. Therefore, noncovalently functionalizing GO with different active species can efficiently improve the catalytic performance of GO. This opens a new way to design and construct noble-metal-free catalysts with enhanced activity and selectivity.
氧化石墨烯（GO）纳米片是很有前景的无贵金属催化剂。然而，GO的催化活性和选择性仍然很低。在此，GO首先通过具有COOH基团的天冬氨酸修饰酸酐通过非共价相互作用进行功能化，以形成A-GO。A-GO比通过无COOH酸酐对GO进行功能化合成的GO和P-GO更具导电性和亲水性。然后，我们将负责吸收光以产生电荷载流子的硫化镉纳米颗粒负载在A-GO上，以制备用于通过HO光还原CO的无贵金属的CdS/A-GO光催化剂。CdS/A-GO表现出比CdS/GO和CdS/P-GO更高的光还原效率。CdS/A-GO的主要碳基光还原产物是CHOH，而CdS/GO和CdS/P-GO的主要碳基光还原产物是CO。导电性和亲水性更强的A-GO引发更有效的电子转移、CO吸附以及HO解离产生氢原子，从而导致CdS/A-GO具有更高的光还原效率和产物变化。此外，天冬氨酸修饰酸酐的COOH基团提供氢原子以促进CdS/A-GO上CO向CHOH的转化。因此，用不同活性物种对GO进行非共价功能化可以有效提高GO的催化性能。这为设计和构建具有增强活性和选择性的无贵金属催化剂开辟了一条新途径。
