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Zhuang, Zechao

Publications and source records attributed to Zhuang, Zechao.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Glycerol Electrooxidation over Precision-Synthesized Gold Nanocrystals with Different Surface Facets

Electrochemical glycerol oxidation (EGO) emerges as a promising route to valorize glycerol, an underutilized byproduct from biodiesel production, into value-added chemicals. This study employed three types of gold (Au) nanocrystals with controlled shapes to elucidate the facet-dependent electrocatalytic behavior in EGO. Octahedral, rhombic dodecahedral, and cubic Au nanocrystals with {111}, {110}, and {100} facets, respectively, were precisely synthesized with uniform size and shape. Rhombic dodecahedra exhibited the lowest onset potential for EGO due to facile AuOH formation, while octahedra showed enhanced electrochemical activity for glycerol oxidation and resistance to poisoning. In-situ FTIR analysis revealed that Au {111} surfaces selectively favored C 2 products, whereas Au {100} surfaces promoted C 3 product formation, highlighting the significant effect of facet orientation on EGO performance and informing catalyst design.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Trends in electrocatalytic activity and stability of transition-metal nitrides

Transition metal nitrides (TMNs) are a class of electrocatalyst support materials similar to transition metal carbides (TMCs) with the advantage of avoiding the issues arising from graphitic carbon surface deposits during synthesis. Inspired by previous studies suggesting that TMCs could be used to reduce Pt loading for the hydrogen evolution reaction (HER), this work explored the feasibility of TMN-supported Pt and Au as HER electrocatalysts. Here this study established a volcano-like trend between electrochemical HER activity and hydrogen-binding energy (HBE) calculated from density functional theory. The Pt/TiN and Au/TiN materials were used to extend knowledge from well-characterized thin films to powder catalysts. In situ X-ray absorption spectroscopy (XAS) measurements provided additional characterization of the Pt/TiN and Au/TiN catalysts under HER conditions. Trends in the electrochemical stability of TMNs were also investigated over a wide range of potentials and pH values, which can be used to guide future studies for TMN-supported electrocatalysts.

58 GEOSCIENCES↗