Piezo-catalysis, which leverages mechanical energy to drive chemical reactions, is emerging as a promising method for sustainable energy production. While the enhancement of piezo-catalytic performance through metal-support interactions is well-documented, the critical influence of the synthesis atmosphere during metal-loaded piezo-catalyst preparation has been a notable gap in the field. To this end, we systematically investigate how different atmospheric conditions during the synthesis of catalysts—without gas flow or with Ar, N₂ and O₂—affect metal dispersion, oxidation states, piezo-carrier dynamics, and electronic structure, and subsequently shape the metal-support interactions and piezo-catalytic activity. ZnO/Au, with Au deposited on ZnO, is selected as the model system, and hydrogen evolution reaction is used as the probe reaction. Our results demonstrate that an oxygen-enriched atmosphere significantly enhances the metal-support interactions, achieving an ultrahigh net hydrogen yield of 16.5 mmol·g⁻¹·h⁻¹ on ZnO/Au, a 3.58-fold increase over pristine ZnO. Specifically, the performance improvements substantially surpass those synthesized under other atmospheric conditions. Conversely, exposure to CO₂ transforms the ZnO support into ZnCO₃, adversely affecting its catalytic activity. These findings reveal the crucial impact of synthesis conditions on piezo-catalyst performance and thereby open new avenues for optimizing catalyst systems for enhanced sustainability.

Fuel cells operated with a reformate fuel such as methanol are promising power systems for portable electronic devices due to their high safety, high energy density and low pollutant emissions. However, several critical issues including methanol crossover effect, CO-tolerance electrode and efficient oxygen reduction electrocatalyst with low or non-platinum usage have to be addressed before the direct methanol fuel cells (DMFCs) become commercially available for industrial application. Here, we report a highly active and selective Mg−Co dual-site oxygen reduction reaction (ORR) single atom catalyst (SAC) with porous N-doped carbon as the substrate. The catalyst exhibits a commercial Pt/C-comparable half-wave potential of 0.806 V (versus the reversible hydrogen electrode) in acid media with good stability. Furthermore, practical DMFCs test achieves a peak power density of over 200 mW cm⁻² that far exceeds that of commercial Pt/C counterpart (82 mW cm⁻²). Particularly, the Mg−Co DMFC system runs over 10 h with negligible current loss under 10 M concentration methanol work condition. Experimental results and theoretical calculations reveal that the N atom coordinated by Mg and Co atom exhibits an unconventional d-band-ditto localized p-band and can promote the dissociation of the key intermediate *OOH into *O and *OH, which accounts for the near unity selective 4e⁻ ORR reaction pathway and enhanced ORR activity. In contrast, the N atom in SAC–Co remains inert in the absorption and desorption of *OOH and *OH. This local coordination environment regulation strategy around active sites may promote rational design of high-performance and durable fuel cell cathode electrocatalysts.

The construction of efficient and durable electrocatalysts with highly dispersed metal clusters and hydrophilic surface for alkaline hydrogen evolution reaction (HER) remains a great challenge. Herein, we prepared hydrophilic nanocomposites of Ru clusters (~ 1.30 nm) anchored on Na⁺, K⁺-decorated porous carbon (Ru/Na⁺, K⁺-PC) through hydrothermal method and subsequent annealing treatment at 500 °C. The Ru/Na⁺, K⁺-PC exhibits ultralow overpotential of 7 mV at 10 mA·cm⁻², mass activity of 15.7 A·mg_Ru⁻¹ at 100 mV, and long-term durability of 20,000 cycles potential cycling and 200 h chronopotentiometric measurement with a negligible decrease in activity, much superior to benchmarked commercial Pt/C. Density functional theory based calculations show that the energy barrier of H–OH bond breaking is efficiently reduced due to the presence of Na and K ions, thus favoring the Volmer step. Furthermore, the Ru/Na⁺, K⁺-PC effectively employs solar energy for obtaining H₂ in both alkaline water and seawater electrolyzer. This finding provides a new strategy to construct high-performance and cost-effective alkaline HER electrocatalyst.

Developing highly stable and active non-Pt oxygen reduction reaction (ORR) electrocatalysts for power generation device raises great concerns and remains a challenge. Here, we report novel truncated Pd tetrahedrons (T-Pd-Ths) enclosed by {111} facets with excellent uniformity, which have both low-coordinated surface sites and distinct lattice distortions that would induce “local strain”. In alkaline electrolyte, the T-Pd-Ths/C achieves remarkable ORR specific/mass activity (SA/MA) of 2.46 mA·cm⁻²/1.69 A·mg_Pd⁻¹, which is 12.3/16.9 and 10.7/14.1 times higher than commercial Pd/C and Pt/C, respectively. The T-Pd-Ths/C also exhibits high in-situ carbon monoxide (CO) tolerance and 50,000 cycles durability with an activity loss of 7.69% and morphological stability. The rotating ring-disk electrode (RRDE) measurements show that a 4-electron process occurs on T-Pd-Ths/C. Theoretical calculations demonstrate that the low-coordinated surface sites contribute largely to the enhancement of ORR activity. In actual direct methanol fuel cell (DMFC) device, the T-Pd-Ths/C delivers superior open-circuit voltage (OCV) and peak power density (PPD) to commercial Pt/C from 25 to 80 °C, and the maximum PPD can reach up to 163.7 mW·cm⁻². This study demonstrates that the T-Pd-Ths/C holds promise as alternatives to Pt for ORR in DMFC device.

It is challenging and desirable to construct Pt-based nanocomposites with oxygen storage function as efficient oxygen reduction reaction (ORR) catalysts for practical proton exchange membrane fuel cells (PEMFCs). Herein, we achieve novel porous nanocomposites of PtCu₃ nanoalloys-embedded in the PWO_x matrix (PtCu₃@PWO_x), which has an oxygen container feature. The PtCu₃@PWO_x/C exhibits an ultrahigh mass activity (MA) of 3.94 A·mg_Pt⁻¹ for ORR, which is 26.3 times as high as the commercial Pt/C and the highest value ever reported for PtCu-based binary system. Theoretical calculations reveal that the compressive strain and d-band center downshift of Pt intrinsically contribute to the excellent ORR performance. In H₂-air PEMFCs at room temperature, furthermore, the PtCu₃@PWO_x/C delivers a high power density (218.6 mW·cm⁻²), much superior to commercial Pt/C (131.6 mW·cm⁻²). In H₂-O₂ PEMFCs, PtCu₃@PWO_x/C outputs a maximum power density of 420.1 mW·cm⁻². This work provides an effective idea for designing oxygen-storing ORR catalysts used for practical room-temperature H₂-air fuel cells.

Recently, the bismuth-rich strategy via increasing the bismuth content has been becoming one of the most appealing approaches to improve the photocatalytic performance of bismuth oxyhalides. However, insights into the mechanism behind the encouraging experiments are missing. Herein, we report the results of the theory-led comprehensive picture of bismuth-rich strategy in bismuth oxyhalide photocatalysts, selecting Bi₅O₇X (X = F, Cl, Br, I) as a prototype. First-principle calculations revealed that the strategy enables good n-type conductivity, large intrinsic internal electric field, high photoreduction ability and outstanding harvest of visible light, and particularly ranked the intrinsic activity of this family: Bi₅O₇F > Bi₅O₇I > Bi₅O₇Br > Bi₅O₇Cl. Designed experiments confirmed the theoretical predictions, and together, these results are expected to aid future development of advanced photocatalysts.