While surface strain engineering in shaped and bimetallic nanostructures offers additional variables for manoeuvring the catalysis, manipulating isotropic strain distributions in nanostructures remains a great challenge to reach higher tiers of the catalyst’s design. Herein, we report an efficient approach to construct a unique class of core/shell palladium–lead (Pd–Pb)/Pd nanosheets (NSs) and nanocubes (NCs) with homogeneous tensile strain along [001] on both the top-Pd and edge-Pd surfaces for boosting oxygen reduction reaction (ORR). These core/shell Pd–Pb/Pd NSs and Pd–Pb/Pd NCs exhibit over 160% and 140% increases in mass activity and over 114% and 98% increases in specific activity when compared with these unshelled counterparts, respectively. Especially, the Pd3Pb/Pd NSs show the ORR mass and specific activities of 0.57 A/mgPd and 1.31 mA/cm2 at 0.90 V versus reversible hydrogen electrode, which are 8.8 (6.5) and 9.4 (9.8) times higher than those of the commercial Pd/C (Pt/C), respectively. The valence band photoemission spectra and first-principles calculations collectively show that the tensile strained Pd shell results in an upshift of the d-band-center of Pd, weakening the chemisorption of oxygenated species due to the contribution of the antibonding orbital. In addition, the Pd3Pb/Pd NSs and NCs with intermetallic core and homogeneous few layers of Pd shell can sustain at least 20 000 potential cycles with negligible activity decay and composition changes. The present work provides a new direction for the design of highly active and stable catalysts for fuel cells and beyond.

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Since photocatalytic N2 to NH3 is a kinetically complex and multielectron reaction, designing efficient materials to fix N2 is highly essential. Herein, we reported that simultaneously introducing oxygen vacancy and doping Fe into BiOCl nanosheets (NSs) can greatly boost the photocatalytic N2 fixation. BiOCl NSs-Fe-5% exhibit the maximum NH3 generation rate of 1.022 mmol g–1 h–1 and durable stability after successive cycling, being one of the best photocatalysts for N2 fixation. This work demonstrates a promising strategy to design efficient photocatalysts for N2 fixation, holding great significance for extensions to other material systems.

The electroreduction of small molecules to high value‐added chemicals is considered as a promising way toward the capture and utilization of atmospheric small molecules. Discovering cheap and efficient electrocatalysts with simultaneously high activity, selectivity, durability, and even universality is desirable yet challenging. Herein, it is demonstrated that Bi2Te3 nanoplates (NPs), cheap and noble‐metal‐free electrocatalysts, can be adopted as highly universal and robust electrocatalysts, which can efficiently reduce small molecules (O2, CO2, and N2) into targeted products simultaneously. They can achieve excellent activity, selectivity and durability for the oxygen reduction reaction with almost 100% H2O2 selectivity, the CO2 reduction reaction with up to 90% Faradaic efficiency (FE) of HCOOH, and the nitrogen reduction reaction with 7.9% FE of NH3. After electrochemical activation, an obvious Te dissolution happens on the Bi2Te3 NPs, creating lots of Te vacancies in the activated Bi2Te3 NPs. Theoretical calculations reveal that the Te vacancies can modulate the electronic structures of Bi and Te. Such a highly electroactive surface with a strong preference in supplying electrons for the universal reduction reactions improves the electrocatalytic performance of Bi2Te3. The work demonstrates a new class of cheap and versatile catalysts for the electrochemical reduction of small molecules with potential practical applications.