Yanxing Zhang

Palladium nanoparticles with high energy facets as a key factor in dissociating O2 in the solvent-free selective oxidation of alcohols

Palladium (Pd) nanocatalysts with high energy facets {110} supported on flower-like hydroxyapatite (F-HAP) were successfully prepared. Based on the experimental data and theoretical calculations, it was found that the O2 dissociation on Pd {110} facets could be key to the performance of Pd nanoparticles in the solvent-free selective oxidation of alcohols.

Density functional study on the mechanism for the highly active palladium monolayer supported on titanium carbide for the oxygen reduction reaction.

The adsorption, diffusion, and dissociation of O2 on the palladium monolayer supported on TiC(001) surface, MLPd/TiC(001), are investigated using ab initio density functional theory calculations. Strong adhesion of palladium monolayer to the TiC(001) support, accompanied by a modification of electronic structure of the supported palladium, is evidenced. Compared with Pt(111) surface, the MLPd/TiC(001) can enhance the adsorption of O2, leading to comparable dissociation barrier and a smaller diffusion barrier of O2. Whilst the adsorption strength of atomic O (the dissociation product of O2) on MLPd/TiC(001) is similar to that on the Pt(111) surface, possessing high mobility, our theoretical results indicate that MLPd/TiC(001) may serve as a good catalyst for the oxygen reduction reaction.

Facile synthesis of silver@carbon nanocable-supported platinum nanoparticles as high-performing electrocatalysts for glycerol oxidation in direct glycerol fuel cells

Novel Ag@C nanocables are successfully synthesized through a hydrothermal self-assembly process, and employed as the support material to fabricate a uniformly distributed Pt nanoparticle electrocatalyst (Pt/Ag@C) for glycerol oxidation reaction (GOR). Electrochemical measurements demonstrate that this Pt/Ag@C catalyst can have both superior electrocatalytic GOR activity and stability, confirming that the Ag@C nanocables should be a great material for supporting the catalyst. Theoretical calculations are also carried out for fundamental understanding of the enhanced catalytic performance of this Pt/Ag@C catalyst. The results show that this Pt/Ag@C catalyst should be a great candidate as the anode catalyst for direct glycerol fuel cells.

Efficient noble metal nanocatalysts supported on HfC(001) for O2 dissociation

The adsorption and dissociation of O2 on the M4 (M=Au, Pd, Pt) clusters supported on HfC(001) (Hafnium Carbide) are investigated using ab initio density functional theory calculations. The geometric and electronic structures are analyzed in detail. It is found that the dissociation barriers of O2 on Au4/HfC(001) (0.26 eV), Pd4/HfC(001) (0.49 eV) and Pt4/HfC(001) (0.09 eV) are much smaller than those on the clean surfaces of HfC(001) (1.60 eV), Au(111) (1.37 eV), Pd(111) (1.0 and 0.91 eV) and Pt(111) (0.27–0.7 eV), respectively. The low dissociation barriers imply that the Pt4/HfC(001) exhibits the highest catalytic activity for O2 dissociation, and the Au4/HfC(001) and Pd4/HfC(001) may also be possible substitutes with lower cost for the current Pt/C catalyst for O2 dissociation. The present study is conductive to designing new efficient noble metal catalyst using HfC support for efficiently promoting O2 dissociation.