A hollow PdCuMoNiCo high-entropy alloy as an efficient bi-functional electrocatalyst for oxygen reduction and formic acid oxidation

Abstract

A hollow PdCuMoNiCo high-entropy alloy on carbon hybrid was developed as a high-performance bi-functional electrocatalyst for the oxygen reduction reaction and formic acid oxidation reaction in an acidic medium.

Facile Solvothermal Synthesis of Pt–Ir–Pd–Rh–Ru–Cu–Ni–Co High-Entropy Alloy Nanoparticles

“…The latter is also a challenge for particle formation from gas-carried droplets 44,49,57,58 and calcination of multi-element metal−organic frameworks or polymer matrices. 46,59 These synthesis parameters are typically better for wet chemistry methods, 25,[31][32][33]60,61 but other challenges such as limited elemental compatibility and use of toxic chemicals are present. The advantages and drawbacks of the published synthesis methods for HEA catalysts have been compared in several recent reviews.…”

“…The mentioned assets make HEAs obvious candidates for energy technology such as proton-exchange membrane electrolysis and alcohol fuel cells, which are likely focal points of future power-to-X technology. The usage of HEAs for electrocatalysis has been investigated theoretically, − and promising experimental results have already been reported for the oxygen reduction reaction (ORR), − hydrogen evolution reaction (HER), − oxygen evolution reaction (OER), − hydrogen oxidation reaction (HOR), CO 2 reduction, methanol/ethanol oxidation, − urea oxidation, glycerol oxidation, and combinations of these. − …”

“…Physical vapor deposition methods and carbothermal shock synthesis have been employed successfully, ,,− but these synthesis techniques are restrictive in their substrate applicability and productivity. The latter is also a challenge for particle formation from gas-carried droplets ,,, and calcination of multi-element metal–organic frameworks or polymer matrices. , These synthesis parameters are typically better for wet chemistry methods, ,− ,, but other challenges such as limited elemental compatibility and use of toxic chemicals are present. The advantages and drawbacks of the published synthesis methods for HEA catalysts have been compared in several recent reviews. − These reviews unanimously state that one of the main challenges in the field is development of synthesis methods with enhanced product control, flexibility, and productivity.…”

d–p Orbital hybridization in RhSn catalyst boosts hydrogen oxidation reaction under alkaline electrolyte

“…[1][2][3][4] The proton exchange membrane fuel cell (PEMFC) is the most advanced fuel cell technology. 4,5 However, under a harsh acidic environment, efficient and stable electrocatalysts for the cathodic oxygen reduction reaction (ORR) are severely limited to platinum (Pt)-based catalysts, impeding the large-scale application of PEMFCs. [5][6][7] Alternatively, under alkaline media, the ORR can be catalyzed by non-Pt electrocatalysts with Pt-like performance, leading to the rapid development of cost-effective alkaline exchange membrane fuel cells.…”

“…4,5 However, under a harsh acidic environment, efficient and stable electrocatalysts for the cathodic oxygen reduction reaction (ORR) are severely limited to platinum (Pt)-based catalysts, impeding the large-scale application of PEMFCs. [5][6][7] Alternatively, under alkaline media, the ORR can be catalyzed by non-Pt electrocatalysts with Pt-like performance, leading to the rapid development of cost-effective alkaline exchange membrane fuel cells. [8][9][10] Nevertheless, for the anodic hydrogen oxidation reaction (HOR), the kinetics declines by over two orders of magnitude when the electrolyte switches from acid to base, even for Pt.…”