Hornwort-like hollow porous MoO3/NiF2 heterogeneous nanowires as high-performance electrocatalysts for efficient water oxidation

Co3 O4 Supported on β-Mo2 C with Different Interfaces for Electrocatalytic Oxygen Evolution Reaction

Interface engineering is an effective strategy for improving the activity of catalysts in electrocatalytic oxygen evolution reaction (OER). Herein, Co3 O4 supported on β-Mo2 C with different interfaces were investigated for electrocatalytic OER. The morphological diversity of β-Mo2 C supports allowed different Co3 O4 -Mo2 C interactions. Various techniques characterized the composition and microstructure of the interface in the composites. Due to the strong interaction between Co3 O4 nanoparticles and β-Mo2 C nanobelts with opposing surface potentials, compact interface was observed between Co3 O4 active species and β-Mo2 C nanobelt support. The compact interface enhanced the conductivity of the material and also regulated the interfacial electron redistribution of Mo and Co atoms, promoting the charge transfer process during OER. In addition, the surface loading of Co3 O4 can effectively improve the hydrophilicity of the surface. β-Mo2 C has the capability in dissociating H2 O molecules. Thus, an example has been carefully demonstrated for interface engineering in electrocatalytic OER.

Ce-Doped Ni-S nanosheets on Ni foam supported NiMoO4 micropillars: fast electrodeposition, improved electrocatalytic activity and ultralong durability for the oxygen evolution reaction in various electrolytes

Developing active, durable, and inexpensive electrocatalysts for the oxygen evolution reaction (OER) is drawing increased interest. Here, a mild hydrothermal-electrodeposition two-step route is designed for the preparation of Ce-doped Ni-S@NiMoO₄ micropillar composites on nickel foam (CeNiS@NiMoO₄/NF). The as-constructed CeNiS@NiMoO₄/NF electrode shows an ultralow overpotential, fast kinetics, superb intrinsic activity and excellent long-term stability for the OER. In 1 M KOH solution, 187 mV overpotential is required to deliver a current density of 10 mA cm^-2 with a Tafel slope of 35.28 mV dec^-1, and in a saline-alkaline solution of 1 M KOH and 0.5 M NaCl, only 260 mV overpotential is needed to reach 100 mA cm^-2, demonstrating its excellent OER performance. The above outstanding electrocatalytic activity is attributed to the influence of CeNiS nanosheets on the surface microstructure of NiMoO₄ micropillars, which not only improves the conductivity of the catalyst, but also increases the surface area, as well as accelerates the escape of gases produced. Compared with other non-precious metal OER electrocatalysts, the as-prepared CeNiS@NiMoO₄/NF presents stronger or close electrocatalytic activity and better durability, which provides a new electrocatalyst selection in practical applications.

Electrochromic Performance and Capacitor Performance of α-MoO3 Nanorods Fabricated by a One-Step Procedure

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.