Rational Design of Core@shell Structured CoS_x@Cu₂MoS₄ Hybridized MoS₂/N,S‐Codoped Graphene as Advanced Electrocatalyst for Water Splitting and Zn‐Air Battery

Abstract

A novel hybrid of small core@shell structured CoSx@Cu2MoS4 uniformly hybridizing with a molybdenum dichalcogenide/N,S‐codoped graphene hetero‐network (CoSx@Cu2MoS4‐MoS2/NSG) is prepared by a facile route. It shows excellent performance toward the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The hybrid exhibits rapid kinetics for ORR with high electron transfer number of ≈3.97 and exciting durability superior to commercial Pt/C. It also demonstrates great potential with remarkable stability for HER and OER, requiring low overpotential of 118.1 and 351.4 mV, respectively, to reach a current density of 10 mA cm−2. An electrolyzer based on CoSx@Cu2MoS4‐MoS2/NSG produces low cell voltage of 1.60 V and long‐term stability, surpassing a device of Pt/C + RuO2/C. In addition, a Zn‐air battery using cathodic CoSx@Cu2MoS4‐MoS2/NSG catalyst delivers a high cell voltage of ≈1.44 V and a power density of 40 mW cm−2 at 58 mA cm−2, better than the state‐of‐the‐art Pt/C catalyst. These achievements are due to the rational combination of highly active core@shell CoSx@Cu2MoS4 with large‐area and high‐porosity MoS2/NSG to produce unique physicochemical properties with multi‐integrated active centers and synergistic effects. The outperformances of such catalyst suggest an advanced candidate for multielectrocatalysis applications in metal‐air batteries and hydrogen production.

The mechanical and electrical properties of direct-spun carbon nanotube mat-epoxy composites

“…Porous electrodes in pseudocapacitors are manufactured by first coating the CNT bundle network with a suitable electrode material, and second by immersing the porous electrodes into a liquid electrolyte [20][21][22][23][24][25][26][27]. In common with many other electrode architectures [28][29][30][31], the specific power of these CNT-based electrodes arises from a high internal surface area over which ionic transport and chemical reactions occur.…”

Interfacial Kinetics Regulation of MoS2/Cu2Se Nanosheets toward Superior High‐Rate and Ultralong‐Lifespan Sodium‐Ion Half/Full Batteries

“…Figure S1 shows the X-ray diffraction (XRD) pattern of Cu 2 MoS 4 , and these obvious peaks are consistent with previous reports. [24,25] Furthermore, the scanning (SEM) and transmission electron microscopy (TEM) images (Figure S2) show its morphology is laminated square-nanosheets with a size of 2 μm × 2 μm. Then, the Cu 2 MoS 4 nanosheet is selenized to obtain the MoS 2 /Cu 2 Se nanocomposite.…”

微纳结构过渡金属化合物能源转化电催化剂研究进展

“…The as-prepared nanomaterials exhibited a platinum-like HER activity with good stability in 0.5 mol L −1 H 2 SO 4 . Nguyen et al [73] engineered a CoS x @Cu 2 MoS 4 -MoS 2 /NSG composite via refluxing the precursors followed by a twostep calcination with controllable heating rate and gas flow rate, the as-prepared material showed a core-shell heterostructure (Fig. 7c, d), which exhibited numerous advantageous physicochemical properties: (i) the Cu and Mo in Cu 2 MoS 4 induced the neighboring S to be effective electrocatalytic active sites, which showed an appropriate oxygen adsorption property and O-O bond cleaving ability.…”