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The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO₂ capture and reduction is essential for improving the conversion efficiency of CO₂ electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO₂ reduction reaction (CO₂RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnO_x catalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueousmore » electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO₂RR selectivity (~90%). This rationally designed triple-phase interface overcomes the issue of limited CO₂ solubility in aqueous electrolytes via proactive CO₂ capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO₂RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO₂RR selectivity (~90%) compared with constant potential (~70%) applied at -0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO₂ capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO₂RR intermediates. Finally, this work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.« less

Direct ethanol fuel cells have been widely investigated as nontoxic and low-corrosive energy conversion devices with high energy and power densities. It is still challenging to develop high-activity and durable catalysts for a complete ethanol oxidation reaction on the anode and accelerated oxygen reduction reaction on the cathode. The materials’ physics and chemistry at the catalytic interface play a vital role in determining the overall performance of the catalysts. Herein, we propose a Pd/Co@N-C catalyst that can be used as a model system to study the synergism and engineering at the solid-solid interface. Particularly, the transformation of amorphous carbon tomore » highly graphitic carbon promoted by cobalt nanoparticles helps achieve the spatial confinement effect, which prevents structural degradation of the catalysts. The strong catalyst-support and electronic effects at the interface between palladium and Co@N-C endow the electron-deficient state of palladium, which enhances the electron transfer and improved activity/durability. The Pd/Co@N-C delivers a maximum power density of 438 mW cm^-2 in direct ethanol fuel cells and can be operated stably for more than 1000 hours. This work presents a strategy for the ingenious catalyst structural design that will promote the development of fuel cells and other sustainable energy-related technologies.« less

Aqueous zinc-ion batteries, in terms of integration with high safety, environmental benignity, and low cost, have attracted much attention for powering electronic devices and storage systems. However, the interface instability issues at the Zn anode caused by detrimental side reactions such as dendrite growth, hydrogen evolution, and metal corrosion at the solid (anode)/liquid (electrolyte) interface impede their practical applications in the fields requiring long-term performance persistence. Despite the rapid progress in suppressing the side reactions at the materials interface, the mechanism of ion storage and dendrite formation in practical aqueous zinc-ion batteries with dual-cation aqueous electrolytes is still unclear. Herein,more » we design an interface material consisting of forest-like three-dimensional zinc-copper alloy with engineered surfaces to explore the Zn plating/stripping mode in dual-cation electrolytes. The three-dimensional nanostructured surface of zinc-copper alloy is demonstrated to be in favor of effectively regulating the reaction kinetics of Zn plating/stripping processes. The developed interface materials suppress the dendrite growth on the anode surface towards high-performance persistent aqueous zinc-ion batteries in the aqueous electrolytes containing single and dual cations. This work remarkably enhances the fundamental understanding of dual-cation intercalation chemistry in aqueous electrochemical systems and provides a guide for exploring high-performance aqueous zinc-ion batteries and beyond.« less

Employing the strong metal-support interaction (SMSI) effect for promoting the catalyst's activity toward the oxygen reduction reaction (ORR) is promising due to the electronic structure optimization and high utilization efficiency of platinum group metal (PGM) catalysts. Metal oxides as alternative supports for PGMs facilitate intrinsic activity and improve durability as compared to conventional carbon supports. However, the restricted mass and electron transfer at the metal/support interface need to be addressed. Herein, to strengthen the interaction at the metal/support interfaces and improve the utilization efficiency of PGM, an ultralow loading of Pd was embedded in a surface-oxygenated PdNiMnO porous film. Themore » Mn-doping was designed to promote surface oxygenation using a facile anodization process that created sufficiently exposed interfaces between Pd and the support, strengthening the SMSI effects at the Pd/oxygenated support interface for enhancing ORR performance. Furthermore, the Ni-containing oxygenated catalyst served as both the active component for the oxygen evolution reaction (OER) and the functional support for stabilizing Pd, making PdNiMnO a bifunctional catalyst for zinc–air flow batteries (ZAFB). As a proof-of-concept, the ZAFB (PdNiMnO) shows a maximal power density of 211.6 mW cm^–2 and outstanding cycling stability for over 2000 h with a minimal voltage gap of 0.69 V at a current density of 10 mA cm^–2, superior to the state-of-the-art catalysts.« less