Bifunctional Palladium Hydride Nanodendrite Electrocatalysts for Hydrogen Evolution Integrated with Formate Oxidation

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing efficient electrocatalysts is crucial for sustainable hydrogen (H2) generation.
• Current methods face challenges in achieving high activity and stability.

Purpose of the Study:

• To synthesize and characterize novel palladium hydride nanodendrites (PdH-NDs).
• To investigate the electrocatalytic performance of PdH-NDs for formate oxidation and hydrogen evolution reactions.
• To correlate material morphology and composition with catalytic activity and stability.

Main Methods:

• Solvothermal synthesis of palladium nanodendrites.
• Chemical hydrogen intercalation to form palladium hydride nanodendrites (PdH-NDs).
• Electrochemical characterization and density functional theory (DFT) calculations.

Main Results:

• PdH-NDs exhibited enhanced electrochemical activity and stability compared to Pd nanodendrites.
• DFT calculations revealed a downshift in the Pd d-band center due to Pd-H ligand effects, weakening intermediate binding.
• An asymmetric formate electrolyzer using PdH-NDs achieved continuous H2 generation at a low voltage of 0.54 V.

Conclusions:

• PdH-NDs demonstrate significant bifunctional electroactivity for formate oxidation and hydrogen evolution.
• The study provides insights into the morphology/composition-performance relationship in palladium hydrides.
• This work paves the way for advanced electrocatalysts in energy-saving electrolysis.