Nickel Cobalt Sulfide Double-Shelled Hollow Nanospheres as Superior Bifunctional Electrocatalysts for Photovoltaics and Alkaline Hydrogen Evolution

Abstract

Transition metal chalcogenides with hollow nanostructures have been considered as promising substitutes as precious metal electrocatalysts for energy conversion and storage. We synthesized NiCoS double-shelled ball-in-ball hollow spheres (BHSs) via a simple solvothermal route and applied them in both dye-sensitized solar cells (DSSCs) and hydrogen evolution reactions (HERs) at the same time, which were clean and sustainable ways to convert energy. Benefiting from their remarkable structure features and advantageous chemical compositions, NiCoS BHSs composed of tiny crystals possessed large surface area, well-defined interior voids, and high catalytic activity. The DSSC with NiCoS BHSs under 100 mW cm irradiation possessed a power conversion efficiency of 9.49% (Pt, 8.30%). Besides, NiCoS BHSs as a HER catalyst also possessed a small onset overpotential (27.9 mV) and a low overpotential (89.7 mV at 10 mA cm) under alkaline conditions. Therefore, this work offers a sensible strategy to synthesize bifunctional electrocatalysts for DSSCs and HERs.

Nanoarchitectonics for Transition‐Metal‐Sulfide‐Based Electrocatalysts for Water Splitting

“…DFT calculations of the surface structures using the surface energy as a descriptor for the catalytic activity revealed that the surface energy of the BHSs) using a facile solvothermal route. [200] The ball-in-ball structure was supposed to form due to the nanoscale Kirkendall effect and the ion exchange reaction. proceeded HER process at overpotential of 41 mV to reach 10 mA cm -2 and a small Tafel slope of 37 mV dec -1 .…”

Novel approach to synthesize NiCo2S4 composite for high-performance supercapacitor application with different molar ratio of Ni and Co

“…The development of sustainable electrochemical energy conversion methods and storage has sparked the interest of researchers aiming to produce devices that offer high power output, a long lifetime, and a short charging time to meet the increasing demand for power in daily life 1,2 . Supercapacitors have emerged as a promising energy storage device in this respect, with outstanding properties that include a high power density, a long cycle life, short response, rapid charging times, moderate energy density, modest maintenance requirements, and safe operation 2–5 .…”

Low‐Cost and Extra‐Simple Preparation of Porous NiS2 Counter Electrode for High‐Efficiency Dye‐Sensitized Solar Cells

“…J lim is the intersection of the anodic or cathodic branch with the y axis. The larger J 0 indicates the higher catalytic activity, whereas the larger J lim means the larger ionic diffusion velocity . The corresponding values of J 0 and J lim are shown in Table .…”