Supported ionic liquid phase-boosted highly active and durable electrocatalysts towards hydrogen evolution reaction in acidic electrolyte

Platinum is generally known as the most effective electrocatalyst for hydrogen evolution reaction because it can greatly lower the overpotential and accelerate the reaction kinetics, while its commercial potential always suffers from scarcity, high cost, low utilization, and poor durability particularly in acidic electrolytes. We herein demonstrate a facile method to improve the hydrogen evolution performance of Pt-based electrocatalysts by simply decorating the-state-of-the-art and commercially available Pt/C with hydrophobic protic ([DBU][NTf2]) or aprotic ([BMIm][NTf2]) ionic liquid. The current densities of [BMIm] @Pt/C and [DBU-FI]@Pt/C with 10% ionic liquid at an overpotential of 40 mV are 2.81 and 4.15 times, respectively, higher than that of the pristine Pt/C. More importantly, ionic liquid-decoration significantly improves the long-term stability of Pt nanoparticles. After 8 h of chronoamperometric measurements, [DBU-FI]@Pt/C and [BMIm]@Pt/C can still retain 83.7% and 78.3% of their original activity, respectively, which is much higher than that of the pristine Pt/C (24.4%). The improved performance of Pt/C decorated with ionic liquid is considered to arise from the improved proton conductivity (particularly for protic ionic liquid) and hydrophobic microenvironment created by the supported ionic liquid phase. The presence of ionic liquid layer not only de-coordinates H* from hydronium ions nearby the Pt nanoparticles, but it also protects Pt nanoparticles from dissolution in the acidic media. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

Decorating platinum-based electrocatalysts with ionic liquid can significantly improve the performance of hydrogen evolution reaction and enhance long-term stability.