Electronic Structure Engineering of Pt-Ni Alloy NPs by Coupling of Gold Single Atoms on N-Doped Carbon for Highly Efficient Oxygen Reduction Reaction and Hydrogen Evolution Reaction.

Improving the catalytic activity and durability of platinum-based alloy catalysts remains a formidable challenge in the context of renewable energy electrolysis applications. Herein, a facile and rapid photochemical deposition strategy for the synthesis of gold single atoms (Au SAs) anchored on N-doped carbon is presented. These Au SAs serve as a charge redistribution support for Pt-Ni alloy nanoparticles (PtNi/Au-NDC), creating an extended electron-donating interface with Pt-Ni alloy sites.

Synergistic effect of Pt-Ni dual single-atoms and alloy nanoparticles as a high-efficiency electrocatalyst to minimize Pt utilization at cathode in polymer electrolyte membrane fuel cells.

Pt-Ni (111) alloy nanoparticles (NPs) and atomically dispersed Pt have been shown to be the most effective catalysts for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs) as well as less expensive compared to pure Pt NPs. To meet reaction kinetic demands and minimize the Pt utilization at cathode in PEMFCs, we propose a novel electrocatalyst composed of dual single-atoms (Pt, Ni) and Pt-Ni alloy NPs dispersed on the surface of N-doped carbon (NDC); collectively, PtNi-NDC. The optimized PtNi-NDC catalyst displays excellent mass activity and durability compared to commercial Pt/C.

Effect of core and surface area toward hydrogen gas sensing performance using Pd@ZnO core-shell nanoparticles.

A versatile hydrogen gas sensor is fabricated using Pd@ZnO core-shell nanoparticles (CSNPs), which were synthesized through a hydrothermal route. Effect of oxidation behavior of Pd core to hydrogen sensing is also investigated for Pd@ZnO CSNPs. Accordingly, Pd@ZnO-2 sensor (core-shell sample was calcined in argon) demonstrates the best performance with respect to Pd@ZnO-1 (core-shell sample was calcined in air) and pure ZnO.

Pb2+ removal from aqueous solution using crab shell treated by acid and alkali.

In order to investigate the process of Pb(2+) removal by crab shell, the effects of pretreatment of crab shell with acid and alkali on Pb(2+) removal by crab shell were examined. In acid treatment of crab shell with HCl for the demineralization of crab shell, Ca(2+) and Mg(2+) in crab shell were largely extracted during the acid treatment and the Pb(2+) removal by acid treated crab shell was very low. The total released Ca(2+) and Mg(2+) amounts in the alkali treated crab shell during Pb(2+) removal were not greatly different from those in the untreated crab shell.

The removal by crab shell of mixed heavy metal ions in aqueous solution.

In order to examine the inhibition effect of other heavy metal ions on the removal by crab shell of heavy metal ions in aqueous solutions, three ions (Pb(2+), Cd(2+), Cr(3+)) were used in single, binary and ternary systems. In single heavy metal ion systems, the removals of Cr(3+) and Pb(2+) were much higher than that of Cd(2+). In binary heavy metal ions systems, Cd(2+) did not affect Pb(2+) removal while Cr(3+) had a severe inhibition effect on the removal of Pb(2+).