Synergistic High Entropy and Inductive Effects in Aerogels Accelerate pH-Universal Hydrogen Evolution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient electrocatalysts for the hydrogen evolution reaction (HER) across the entire pH range is a significant scientific challenge.
• Current electrocatalysts often exhibit pH-dependent performance, limiting their practical applications.

Purpose of the Study:

• To report a novel class of high-entropy aerogel alloys with pH-universal HER performance.
• To investigate the key features contributing to the enhanced electrocatalytic activity.

Main Methods:

• Synthesis of high-entropy aerogel alloys.
• Electrochemical measurements including overpotential determination at 10 mA cm⁻² in acidic, neutral, and alkaline media.
• Analysis of structural and electronic properties to understand catalytic mechanisms.

Main Results:

• The developed high-entropy aerogel alloys demonstrate remarkable and pH-universal HER performance.
• The best-performing X-La (X = PtPdRuOs) aerogel exhibited low overpotentials of 2.3 mV (acidic), 28.8 mV (neutral), and 25.3 mV (alkaline) at 10 mA cm⁻².
• The excellent activity is attributed to a porous architecture, high-entropy effects, and strong inductive effects.

Conclusions:

• High-entropy aerogel alloys represent a promising design strategy for pH-universal HER electrocatalysts.
• The synergistic effects within these materials significantly enhance catalytic activity and water activation.
• This work paves the way for robust catalysts applicable in diverse electrochemical environments.