Zhang Qin, Zhang Xiaoxiang, Wang Junzhong, Wang Congwei
CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, People's Republic of China.
Nanotechnology. 2021 Jan 15;32(3):032001. doi: 10.1088/1361-6528/abbd70.
Supported metal nanostructures are the most extensively studied heterogeneous catalysts, benefiting from easy separation, regeneration and affordable cost. The size of the supported metal species is one of the decisive factors in determining the activity of heterogeneous catalysts. Particularly, the unsaturated coordination environment of metal atoms preferably act as the active centers, minimizing these metal species can significantly boost the specific activity of every single metal atom. Single-atom catalysts/catalysis (SACs), containing isolated metals atomically dispersed on or coordinated with the surface of a support material, represent the ultimate utilization of supported metals and maximize metal usage efficiency. Graphene, a two-dimensional star material, exhibiting extraordinary physical and chemical properties, has been approved as an excellent platform for constructing SACs. When atomically dispersed metal atoms are strongly anchored on the graphene surface, featuring ultra-high surface area and excellent electronic properties, SACs offer a great potential to significantly innovate the conventional heterogeneous catalysis, especially in the field of electrocatalysis. In this review, a detailed discussion of graphene-supported SACs, including preparation approaches, characterization techniques and applications on typical electrocatalytic reactions is provided. The advantages and unique features of graphene-supported SACs as efficient electrocatalysts and the upcoming challenges for improving their performance and further practical applications are also highlighted.
负载型金属纳米结构是研究最为广泛的多相催化剂，具有易于分离、再生且成本低廉的优点。负载型金属物种的尺寸是决定多相催化剂活性的关键因素之一。特别地，金属原子的不饱和配位环境通常充当活性中心，将这些金属物种的尺寸减小到最小可以显著提高单个金属原子的比活性。单原子催化剂/催化（SACs）包含原子级分散在载体材料表面或与载体材料表面配位的孤立金属原子，代表了负载型金属的极致利用并最大化了金属使用效率。石墨烯作为一种二维明星材料，具有非凡的物理和化学性质，已被证明是构建单原子催化剂的优异平台。当原子级分散的金属原子牢固地锚定在具有超高表面积和优异电子性质的石墨烯表面时，单原子催化剂在显著创新传统多相催化方面具有巨大潜力，尤其是在电催化领域。在本综述中，我们详细讨论了石墨烯负载的单原子催化剂，包括其制备方法、表征技术以及在典型电催化反应中的应用。同时也强调了石墨烯负载的单原子催化剂作为高效电催化剂的优势和独特特性，以及在提高其性能和进一步实际应用方面即将面临的挑战。
