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[Display omitted] • PEI-Au NDs is obtained by a simple one-step reduction approach. • The electronic effect induced by PEI improves the electrocatalytic activity of PEI-Au NDs for GAER. • DFT calculations reveal the PEI-Au(1 1 1) surface possess stronger gluconic acid adsorption. The gluconic acid electroreduction reaction (GAER) coupled with renewable energy is a carbon-free and highly promising biomass utilization route. However, this process still suffers from low conversion efficiency and poor selectivity due to the competitive hydrogen evolution reaction. Some organic amine molecules can not only serve as surfactants to synthesize noble-metal based catalysts with special morphologies, but also can further optimize the catalytic activity of metal surfaces by modulating their electronic structure. Herein, polyethyleneimine (PEI) functionalized gold nanodendrites (PEI-Au NDs) are applied as an efficient electrocatalyst for GAER, in which the production rate and Faradaic efficiency of glucose on PEI-Au NDs reaches to 9.86 μg h−1 mg cata −1 and 15.7 % at − 0.80 V vs. RHE, respectively. The mechanism study through density functional theory calculations reveals that the adsorbed PEI molecule exhibits an electron donating-effect, which can promote the adsorption process of gluconic acid molecules on the Au(1 1 1) plane and the subsequent reduction process. This work offers a novel pathway to rational regulate the adsorption properties and electronic structures of noble metal-based electrocatalysts through chemical functionalization strategy. [ABSTRACT FROM AUTHOR]

RhCu-BMLs with different Rh/Cu molar ratios is synthesised by the high-temperature cyanogel-reduction method. The electronic structure of Rh was optimized by the introduction of Cu atoms, which effectively improves the selectivity of Rh 3 Cu 1 -BMLs for the GEOR. This work provides meaningful insight into the design of advanced electrocatalysts for highly selective GEOR. [Display omitted] • Ultrathin RhCu-BMLs were constructed by the high-temperature cyanogel-reduction method. • RhCu-BMLs showed big surface area, fast mass transport, and optimized electronic structure. • RhCu-BMLs exhibited excellent mass activity (579.3 A g Rh −1) for the GEOR. • RhCu-BMLs revealed a higher selectivity (78.7%) for glyceric acid. The selective electro-oxidation reaction represents an efficient and environmentally friendly pathway to produce value-added chemicals from glycerol. Herein, we introduce a high-temperature cyanogel-reduction method to synthesize ultrathin RhCu bimetallenes (RhCu-BMLs) with varying Rh/Cu molar ratios and investigate their catalytic activity and selectivity for the glycerol electro-oxidation reaction (GEOR). Among these catalysts, the as-prepared Rh 3 Cu 1 -BMLs exhibit outstanding mass activity (579.3 A g Rh −1) for the GEOR under alkaline conditions, marking a 2.32-fold enhancement in mass activity (249.6 A g Rh −1) relative to single-component Rh metallens (Rh-MLs). Meanwhile, both experimental characterizations and theoretical calculations reveal that Cu atoms can attenuate OH− adsorption and block the oxygen insertion reaction for the generation of tartaric acid due to the electronic effect. Consequently, Rh 3 Cu 1 -BMLs achieve a remarkable 78.7 % selectivity for generating glyceric acid during GEOR. This work provides an important reference for fabricating bimetallic Rh-based catalysts and advancing the selectivity and activity in GEOR. [ABSTRACT FROM AUTHOR]

• CoCO 3 PNSs are synthesized a facile precipitation transformation method. • The big discrepancy is inherent driving force for the generation of CoCO 3 PNSs. • CoCO 3 PNSs are consisted of tiny subnanorods with ca. 50 nm length and 5 nm diameter. • CoCO 3 PNSs reveal excellent electrocatalytic activity and durability for OER. • CoCO 3 PNSs can transform into the mixture of Co(OH) 2 and CoOOH during OER. Cost-effective nonprecious metal nanostructures are considered as highly promising electrocatalysts towards oxygen evolution reaction (OER). Optimizing their morphologies is an efficient strategy to enhance the electroactivity and durability of various electrocatalysts for practical application. Herein, porous cobalt carbonate hydroxide nanospheres (CoCO 3 PNSs) are successfully synthesized by using calcium carbonate (CaCO 3) nanospheres as a reaction precursor and self-template via a facile precipitation transformation method. Mainly, the solubility constant K sp (CoCO 3) = 1.4 × 10−13 of CoCO 3 is much lower than that K sp (CaCO 3) = 2.8 × 10−9 of CaCO 3 , resulting in the successful transformation of CaCO 3 nanospheres to CoCO 3 PNSs. Physical characterizations reveal that CoCO 3 PNSs consist of many tiny subnanorods (length of 50 nm, diameter of 5 nm), which have a high surface area and abundant channels between subnanorods. Compared to irregular cobalt carbonate hydroxide nanoparticles, CoCO 3 PNSs reveal enhanced OER performance in KOH solution, including a low overpotential of 310 mV and a small Tafel slope of 56 mV dec−1. [ABSTRACT FROM AUTHOR]