Li Fang, Zhou Haiping, Fan Jiajie, Xiang Quanjun
State Key Laboratory of Electronic Thin Film and Integrated Devices, School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, PR China.
School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 610054, PR China.
J Colloid Interface Sci. 2020 Jun 15;570:11-19. doi: 10.1016/j.jcis.2020.02.108. Epub 2020 Feb 27.
Amine-functionalized graphitic carbon nitride (g-CN) decorated with Au nanoparticles (CN/Au) was prepared by N plasma treatment of g-CN powders impregnated with HAuCl·3HO. Well-dispersed Au nanoparticles with a small particle size were deposited on g-CN nanosheets. In addition, the amino group was introduced into the CN/Au system. Without the addition of cocatalyst and sacrificial agent, CN/Au exhibited enhanced photocatalytic activity for CO reduction under visible-light irradiation. CO and CH evolution rates of CN/Au reached 28.3 and 1.3 μmol·h·g, which were 7.6 and 2.6 times higher than those of pristine g-CN (CN-0), respectively. The enhanced activity can be explained by these factors. (1) The introduced amino group improved the adsorption capacity of CN/Au for CO; (2) the hot electrons generated by Au nanoparticles activated the surrounding electrons through energy transfer and caused local temperature to rise, increasing the efficiency of the photoreduction reaction of CO; (3) the Schottky junction between Au and g-CN promoted the migration of electrons from g-CN to Au nanoparticles, suppressing the recombination of the carriers. Time-of-flight secondary ion mass spectrometry confirmed the introduction of amino groups, and solid-state C nuclear magnetic resonance spectra provided a support for inferring the position of the amino group.
通过对浸渍有 HAuCl·3H₂O 的 g-CN 粉末进行 N 等离子体处理，制备了用 Au 纳米颗粒修饰的胺官能化石墨相氮化碳（g-CN）（CN/Au）。尺寸小且分散良好的 Au 纳米颗粒沉积在 g-CN 纳米片上。此外，氨基被引入到 CN/Au 体系中。在不添加助催化剂和牺牲剂的情况下，CN/Au 在可见光照射下对 CO 还原表现出增强的光催化活性。CN/Au 的 CO 和 CH₄ 析出速率分别达到 28.3 和 1.3 μmol·h⁻¹·g⁻¹，分别比原始 g-CN（CN-0）高 7.6 倍和 2.6 倍。活性增强可由以下因素解释：（1）引入的氨基提高了 CN/Au 对 CO 的吸附能力；（2）Au 纳米颗粒产生的热电子通过能量转移激活周围电子并导致局部温度升高，提高了 CO 光还原反应的效率；（3）Au 和 g-CN 之间的肖特基结促进了电子从 g-CN 向 Au 纳米颗粒的迁移，抑制了载流子的复合。飞行时间二次离子质谱证实了氨基的引入，固态¹³C 核磁共振谱为推断氨基位置提供了支持。
