Interface‐Defect‐Rich In‐Mo Codoped Pd Metallene for Enhanced C1 Selectivity During Electrocatalytic Ethanol Oxidation

Why It Matters

The breakthrough dramatically improves the efficiency and durability of direct ethanol fuel cells, positioning them as a more viable clean‑energy technology for transportation and stationary power markets.

Key Takeaways

• In‑Mo codoped Pd metallene reaches 73.68% C1 selectivity.
• Mass activity hits 4,274 mA mg⁻¹, 12× commercial Pd/C.
• Interface defects boost OH* adsorption, suppress CO* poisoning.
• Catalyst retains 75% activity after extensive cycling.
• Wet‑chemical synthesis offers scalable route for high‑performance EOR catalysts.

Pulse Analysis

Direct ethanol fuel cells (DEFCs) have long been touted as a low‑emission alternative to gasoline, yet their commercial rollout stalls because palladium‑based catalysts struggle to break the stubborn C‑C bond in ethanol. Conventional Pd/C materials suffer from rapid CO poisoning and modest activity, limiting power density and lifespan. By engineering the catalyst at the atomic level—introducing indium and molybdenum into the palladium lattice while generating a high density of interface defects—researchers have tackled both the kinetic and poisoning challenges in one step.

The In‑Mo co‑doped Pd metallene exhibits a striking 73.68% C1 pathway selectivity, meaning most ethanol molecules are fully oxidized to CO₂ rather than partially to acetaldehyde or acetic acid. This selectivity translates into a mass activity of 4,274 mA mg⁻¹ and a specific activity of 8.36 mA cm⁻², outperforming commercial Pd/C by more than an order of magnitude. In‑situ spectroscopic studies and DFT calculations reveal that the added indium and molybdenum modify the electronic structure, strengthening OH* adsorption that facilitates CO* removal while simultaneously lowering the energy barrier for C‑C bond cleavage.

Beyond the laboratory, the catalyst’s synthesis relies on a scalable wet‑chemical method, lowering production costs and easing integration into existing fuel‑cell manufacturing lines. Its robust cycling stability—maintaining 75% of initial activity after prolonged operation—addresses durability concerns that have plagued DEFCs. As automakers and grid operators seek greener power sources, such high‑performance, cost‑effective ethanol oxidation catalysts could accelerate the adoption of DEFCs in hybrid vehicles, portable generators, and remote micro‑grids. Continued optimization and pilot‑scale testing will be key to translating these lab gains into market‑ready solutions.