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Metallic aerogels, as featured by high surface area, porosity, and self‐supported metal skeleton, are regarded as an ideal platform for developing next‐generation electrocatalysts. However, the precise adjustment of their skeleton nanostructure to enhance catalytic properties remains significantly underexplored. Herein, inspired by the impact of the metal atoms' coordination number on their reactivity, we devised and prepared dendritic Pt aerogels (DPAs) via a facile sol‐gel method. The synergy of aerogel structure and coordinatively distinct catalytic sites from dendritic morphology enables DPAs to exhibit markedly improved electrocatalytic activity and stability for methanol oxidation reaction. The mass activity and specific activity of DPAs are 1.28 A mgPt−1 and 1.5 mA cmPt−2, which are 4.1 and 3.2 times higher than those of commercial Pt/C, respectively. [ABSTRACT FROM AUTHOR]

The electrocatalytic oxidation of glucose plays a vital role in biomass conversion, renewable energy, and biosensors, but significant challenges remain to achieve high selectivity and high activity simultaneously. In this study, we present a novel approach for achieving complete glucose electrooxidation utilizing Cu‐based metal‐hydroxide‐organic framework (Cu‐MHOF) featuring coordinatively unsaturated Cu active sites. In contrast to traditional Cu(OH)2 catalysts, the Cu‐MHOF exhibits a remarkable 40‐fold increase in electrocatalytic activity for glucose oxidation, enabling exclusive oxidation of glucose into formate and carbonate as the final products. The critical role of open metal sites in enhancing the adsorption affinity of glucose and key intermediates was confirmed by control experiments and density functional theory simulations. Subsequently, a miniaturized nonenzymatic glucose sensor was developed showing superior performance with a high sensitivity of 214.7 μA mM−1 cm−2, a wide detection range from 0.1 μM to 22 mM, and a low detection limit of 0.086 μM. Our work provides a novel molecule‐level strategy for designing catalytically active sites and could inspire the development of novel metal–organic framework for next‐generation electrochemical devices. [ABSTRACT FROM AUTHOR]

Nowadays, great efforts have been spent on addressing concerns over energy and environmental crises. Among these efforts, electrocatalysis is widely recognized and studied for its high efficiency and easy processability. As a class of emerging electrocatalysts, metal aerogels (MAs) stand out in the last decade. In virtue of their three-dimensional conductive pathways, their library of catalytically/optically active sites, and their robust network structures, MAs have unique advantages in electrocatalysis. However, due to the short history of MAs, there is insufficient research on them, leaving significant room for material design and performance optimization. This perspective will mainly focus on electrocatalysis with MAs, aiming to summarize the state-of-the-art progress and to guide the on-target design of efficient MAs-based electrocatalysts towards energy- and environment-related applications. [ABSTRACT FROM AUTHOR]

The lack of an efficient and stable electrocatalyst for oxygen evolution reaction (OER) greatly hinders the development of various electrochemical energy conversion and storage techniques. In this study, we report a facile synthesis of FeCoNiCuIr high-entropy alloy nanoparticles (HEA NPs) by a one-step heat-up method. The involvement of glucose made the NPs grow uniformly and increased the valence of Ir. The resulting FeCoNiCuIr NPs exhibit excellent OER performance in alkaline solution, with a low overpotential of 360 mV to achieve a current density of 10 mA cm−2 at a Tafel slope of as low as 70.1 mV dec−1. In addition, high stability has also been observed, which remained at 94.2% of the current density after 10 h constant electrolysis, with a constant current of 10 mA cm−2. The high electrocatalytic activity and stability are ascribed to the cocktail effect and synergistic effect between the constituent elements. Our work holds the potential to be extended to the design and synthesis of high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is considered as one of the major roadblocks for many renewable electrochemical energy technologies, such as water splitting, rechargeable metal‐air batteries. Thus the development of efficient and low‐cost OER electrocatalysts has achieved a lot of research and development attention. Aerogels, as featured by large surface area, high porosity, and self‐supportability, provide an excellent platform for the design of efficient electrocatalysts. This review summarizes the recent progress of the aerogel‐based design of catalysts in tackling the challenges in the field of OER electrocatalysis. The correlation between catalyst design strategy and catalytic performances is evaluated to provide a roadmap for the development of aerogel‐based OER electrocatalysts. Thereafter, the current state of our understanding of the application of the aerogel concept in OER electrocatalysis is provided, which could serve as a guide to the development of future aerogel electrocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: The development of core–shell structures remains a fundamental challenge for pure metallic aerogels. Here we report the synthesis of PdxAu‐Pt core–shell aerogels composed of an ultrathin Pt shell and a composition‐tunable PdxAu alloy core. The universality of this strategy ensures the extension of core compositions to Pd transition‐metal alloys. The core–shell aerogels exhibited largely improved Pt utilization efficiencies for the oxygen reduction reaction and their activities show a volcano‐type relationship as a function of the lattice parameter of the core substrate. The maximum mass and specific activities are 5.25 A mgPt−1 and 2.53 mA cm−2, which are 18.7 and 4.1 times higher than those of Pt/C, respectively, demonstrating the superiority of the core–shell metallic aerogels. The proposed core‐based activity descriptor provides a new possible strategy for the design of future core–shell electrocatalysts. [ABSTRACT FROM AUTHOR]

One plausible approach to endow aerogels with specific properties while preserving their other attributes is to fine-tune the building blocks. However, the preparation of metallic aerogels with designated properties, for example catalytically beneficial morphologies and transition-metal doping, still remains a challenge. Here, we report on the first aerogel electrocatalyst composed entirely of alloyed PdNi hollow nanospheres (HNSs) with controllable chemical composition and shell thickness. The combination of transition-metal doping, hollow building blocks, and the three-dimensional network structure make the PdNi HNS aerogels promising electrocatalysts for ethanol oxidation. The mass activity of the Pd83Ni17 HNS aerogel is 5.6-fold higher than that of the commercial Pd/C catalyst. This work expands the exploitation of the electrocatalysis properties of aerogels through the morphology and composition control of its building blocks. [ABSTRACT FROM AUTHOR]