Collaborative Innovation Center of Advanced Functional Composites & School of Physics and Electronic Information , Huaibei Normal University , Huaibei , Anhui 235000 , P. R. China.
College of Physics and Energy , Fujian Normal University , Fuzhou , Fujian 350007 , P. R. China.
Inorg Chem. 2018 Oct 15;57(20):13020-13026. doi: 10.1021/acs.inorgchem.8b02294. Epub 2018 Oct 4.
Design and development of a single atomic catalyst with high activity is desirable but proved to be very challenging in the renewable energy conversion and storage technologies. As a classic carbon material, graphene has many excellent properties and thus may be a good support to stabilize the isolated metal atoms. However, the oxygen evolution activity of a single cobalt atom supported on graphene is still very low. To improve its performance, support modification has been carried out based on a density functional theory framework for the design predication. In our theoretical study, two nitrogen formats are incorporated to the graphene substrates, including graphitic nitrogen and pyridine-like nitrogen, which are usually observed in experiment. The oxygen evolution process has been envisaged on these single cobalt atom catalysts via gas phase adsorption calculation. The electronic structure on the single Co active site can be effectively regulated by the support modification, which will contribute to its enhanced performance. Henceforth, free energy change diagrams, partial density of states, Raman spectra, and charge density difference are discussed. It is suggested that incorporating pyridine-like nitrogen on graphene is an ideal approach for the supported Co atom to achieve high OER activity, opening up new opportunity for the preparation and application of highly active and stable single atomic catalysts.
设计和开发具有高活性的单原子催化剂是人们所期望的,但在可再生能源转化和存储技术中被证明是极具挑战性的。石墨烯作为一种经典的碳材料,具有许多优异的性能,因此可能是稳定孤立金属原子的良好载体。然而,负载在石墨烯上的单个钴原子的析氧活性仍然很低。为了提高其性能,基于密度泛函理论框架进行了载体改性设计预测。在我们的理论研究中,将两种氮形式(石墨氮和吡啶氮)引入到石墨烯基底中,这两种氮形式通常在实验中观察到。通过气相吸附计算来设想这些单钴原子催化剂上的析氧过程。载体改性可以有效地调节单钴活性位的电子结构,从而有助于提高其性能。因此,我们讨论了自由能变化图、部分态密度、拉曼光谱和电荷密度差。研究表明,在石墨烯上引入吡啶氮是负载钴原子实现高 OER 活性的理想途径,为制备和应用高活性和稳定的单原子催化剂开辟了新的机会。