Search

Herein we demonstrate a surface engineering strategy, namely, decorating Au on the surface of bimetallic PtFe nanocatalysts, to effectively decrease the adsorption energy of CO on the Pt center, which promotes the electrocatalytic activity towards methanol oxidation, far better than those of PtFe and commercial Pt/C catalysts. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) are a family of layer materials that receive heightened attention. Herein a ternary NiFeMn-LDH is investigated with superior oxygen evolution activity, which is attributed to the Mn4+ doping in the intralayer, which modifies the electronic structure and improves the conductivity of the electrocatalyst. [ABSTRACT FROM AUTHOR]

Developing an efficient electro-catalyst for water oxidation is essential for improving the performance, which holds the key for a number of energy conversion and storage devices. Here we report an effective method for fabricating a Ni–Co–O@Ni–Co–S hierarchical nanoarray, which showed a significantly improved activity relative to Ni–Co–O nanowire arrays for oxygen evolution reactions. The enhanced performance was attributed to the secondary formed Ni–Co–S nanoplatelets which not only acted as efficient electrocatalysts, but also facilitated the electrolyte penetration and increased the surface area. [ABSTRACT FROM AUTHOR]

The performance of pseudocapacitors usually depends largely on careful manipulation of nano-architectures and suitable composition of the active materials. Herein, NiTi layered double hydroxide (LDH) thin films with uniform density were synthesized by a process including two hydrothermal treatment steps and the composition of the hexagonal NiTi-LDH nanosheets was tunable in a relatively wide range. The obtained NiTi-LDH films on nickel foam show a high areal capacitance of 10.37 F cm−2 at 5 mA cm−2, and good cycling stability (86% of its initial value was preserved after 1000 charge–discharge cycles), much better than β-Ni(OH)2 and basic nickel hydroxides carbonate {Ni2(OH)2CO3·4H2O} films. It is indicated that NH3·H2O in the reaction solution played some important roles including enlarging the particle size, focusing the size distribution, and regulating the stacking modes of NiTi-LDH on nickel foam. This work demonstrated the importance of homogeneous dispersion of Ti atoms in layered nanostructures used in supercapacitors. [ABSTRACT FROM AUTHOR]

Ni0.25Co0.75(OH)2 hierarchical nanowire@nanoplatelet arrays were prepared by an in situ conversion from Ni0.5Co1.5(OH)2CO3 nanowire arrays in a highly concentrated basic solution at room temperature. These unique hierarchical nanoarrays showed a 7 times larger areal capacitance and better rate capability than the precursive one-dimensional nanowire arrays. [ABSTRACT FROM AUTHOR]

Amorphous MoS2 porous thin films (denoted as MoS2 PTFs) with high activity towards hydrogen evolution reaction (HER) were fabricated by in situ sulfuration of a Mo substrate. A small overpotential (∼120 mV) and a low Tafel slope (∼41 mV dec−1) can be observed and their excellent performance was ascribed to the combination of the amorphous feature, porous structure and optimized thickness. [ABSTRACT FROM AUTHOR]

β-Ni(OH)2was constructed into a three-dimensional mesoporous film on Ni foam with ultra-thin (∼6 nm) primary nanowalls showing ultrahigh specific capacitance (2675 F g−1) and excellent cycling performance (>96% for 500 cycles). The capacitance was higher than theoretical value possibly due to the combination of Faradic and electrical double-layer capacitances. [ABSTRACT FROM AUTHOR]

Developing high-efficiency electrocatalysts for nitrate-to-ammonia transformation holds significant promise for the production of ammonia, a crucial component in agricultural fertilizers and as a carbon-free energy carrier. In this study, we propose a viable strategy involving sulfur doping to modulate both the microstructure and electronic properties of CoSe 2 for nitrate reduction. This approach remarkably enhances the conversion of nitrate to ammonia by effectively regulating the adsorption capability of nitrogenous intermediates. Specifically, sulfur-doped CoSe 2 nanowires (S-CoSe 2 NWs) exhibit a peak faradaic efficiency of 93.1% at -0.6 V vs. RHE and achieve the highest NH 3 yield rate of 11.6 mg h -1 cm -2 . Mechanistic investigations reveal that sulfur doping facilitates the creation of highly charged active sites, which enhance the adsorption of nitrite and subsequent hydrogenation, leading to improved selectivity towards ammonia production.

Fabricating active materials into specific macrostructures is critical in the pursuit of high electro-catalytic activity. Herein we demonstrate that a three-dimensional (3D) architecture of NiFe layered double hydroxide (NiFe-LDH) significantly reduced the onset potential, yielded high current density at small overpotentials, and showed outstanding stability in electrochemical oxygen evolution reaction.

Amorphous MoS2 porous thin films (denoted as MoS2 PTFs) with high activity towards hydrogen evolution reaction (HER) were fabricated by in situ sulfuration of a Mo substrate. A small overpotential (~120 mV) and a low Tafel slope (~41 mV dec(-1)) can be observed and their excellent performance was ascribed to the combination of the amorphous feature, porous structure and optimized thickness.