水热法制备镍负载硫磷双掺杂石墨烯电极及其电催化析氢性能研究

Study on the preparation of Ni/SPG electrode by hydrothermal method and its electrocatalytic hydrogen evolution performance

设计一种高活性、高稳定性的非贵金属基催化剂,对电催化析氢的应用具有重要意义。以硫酸和植酸为硫磷掺杂剂,采用水热法合成了硫磷共掺杂石墨烯(SPG);随后,采用简单的醇热法制备了直接生长在SPG上的Ni基纳米材料(Ni/SPG)。制备的Ni/SPG电催化剂表现出杰出的析氢性能,其阻抗极低(0.48Ω),电化学活性表面积极好(32.62m^(2)/g),起始过电位低(115mV),并且具有优秀的Tafel斜率(115mV/dec)和良好的循环稳定性(5000个循环伏安循环)。这些显著的电催化性能归因于S和P双掺杂石墨烯产生更多暴露的活性中心和表面缺陷,使得小晶粒尺寸的Ni均匀地分散在其表面,并促进了它们之间的电子传输。

It is of great significance to design a non-noble metal based catalyst with high activity and stability for the application of electrocatalytic hydrogen evolution.Sulfur phosphorus co-doped graphene(SPG) was successfully synthesized via a simple hydrothermal method using sulfuric acid and phytic acid as dopants.Subsequently,the nickel based nanomaterials grown directly on SPG(named Ni/SPG) were prepared by a simple alcohol thermal method.The prepared Ni/SPG electrocatalyst demonstrated excellent hydrogen evolution performance,such as very low impedance(0.48Ω),active electrochemical surface(32.62 m^(2)/g),low initial overpotential(115 mV),excellent Tafel slope(115 mV/dec) and good cycle stability,and so on.These remarkable electrocatalytic properties were attributed to the more exposed active centers and surface defects of S and P co-doped graphene,which made the Ni with small size evenly dispersed on its surface and promoted the electronic transmission between them.