Monodispersed platinum nanoparticles embedded in Ni3S2-containing hollow carbon spheres with ultralow Pt loading and high alkaline hydrogen evolution activity

• Published in: Electrochimica acta 2019-09, Vol.318, p.590-596
• Main Authors: Xu, Liang, Zhai, Xiaoying, Lin, Weiguo, Chen, Xu, Li, Feng, Yang, Wensheng
• Format: Article
• Language: English
• Subjects: Carbon; Electrocatalysts; Electron transport; Heterostructures; High-mass-activity; Hollow carbon spheres; Hydrogen evolution reaction; Hydrogen evolution reactions; Nanoparticles; Nickel sulfide; Platinum; Pt-Ni3S2 heterostructures; Substrates
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2019.06.116

The design and fabrication of efficient Pt-based electrocatalysts with ultralow-loading but high-mass-activity for hydrogen evolution reaction (HER) in alkaline media is of significant importance. Herein, we report the monodispersed platinum nanoparticles (PtNPs) with an ultralow Pt loading (3.6 μg per electrode area (cm2)) embed in Ni3S2-containing hollow carbon spheres as HER catalysts. Notably, the as-prepared electrocatalyst exhibits a mass activity of 7.6 A gPt−1 at an overpotential of 70 mV, which is 8.5 times higher than that of commercial Pt/C and is among the highest levels of reported Pt-based HER electrocatalysts in alkaline conditions. This electrocatalyst also exhibits excellent HER performance with an overpotential of 42 mV reaching an area current of 10 mA cm−2 and significantly improved stability. The outstanding HER performance is attributed to the hollow and porous carbon spherical structure, as well as highly dispersed PtNPs that provide more active sites and facilitate proton/electron transport. Meanwhile, the nickel-containing layered precursors convert to some Ni3S2 NPs which guarantees the formation of Pt-Ni3S2 heterostructures on the carbon substrate and thus further enhance the activity of PtNPs. This work provides an effective strategy to simultaneously regulate the nanostructure and active site of Pt-containing carbon-based HER electrocatalysts. [Display omitted] •PtNPs embedded in Ni3S2-containing hollow carbon spheres was synthesized.•The material exhibits superior HER activity with mass activity of 7.6 A gPt−1.•The hollow carbon spherical structure promotes the exposure of active sites.•The monodispersed PtNPs increases the atom utilization of Pt.•The highly-dispersed Pt-Ni3S2 heterostructure promotes the HER kinetics.