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Developing highly efficient electrocatalysts for selective glycerol oxidation reaction (GOR) is crucial to implement biomass valorization and to advance the energy conversion efficiency of glycerol fuel cells. Herein, a hybrid alkali-acid direct glycerol fuel cell (DGFC) that can not only deliver a high power density but also enable glycerol valorization conversion is demonstrated. Such double-benefits electrochemical device is implemented by in situ growth of FeCoNiCrMnS 2 nanoparticles on carbon cloth (FeCoNiCrMnS 2 /CC) as anode, which exhibits high activity and selectivity for GOR with low overpotential and high Faradaic efficiency toward the formate product. Based on the results of finite element method simulations of element distribution on FeCoNiCrMnS 2 , the electrocatalytic sites was investigate by density functional theory in conjunction with Monte Carlo and machine learning simulations and confirmed that the desired catalytic properties primarily originate from the Ni and Co sites, while Cr and Mn optimized the electronic structure of these sites. The as-developed DGFC can release a maximum peak power density of 50.1 mW cm−2 and stably generate formate with high selectivity. The present work may inspire to contrive the newly advanced energy device and provide fresh impetus for the development of newly high-entropy materials for a variety of application. [Display omitted] • High-entropy alloy electrocatalysts of FeCoNiCrMnS 2 is developed for glycerol oxidation • The hybrid acid/alkali DGFC is proposed to simultaneously produce electricity and upgrade glycerol • The fuel cell can produce formate with an FE of exceeding 90 % and release a peak power density of 50.1 mW cm−2 • Combining DFT with MC and ML simulations unveil the crucial role of multiple elements in electrocatalysis [ABSTRACT FROM AUTHOR]

Exploring high-activity electrocatalysts for water electrolysis is a pivotal field of hot research as hydrogen is a very promising renewable energy source and bountiful in supply. Understanding the structure–composition–property relationships is the key for engineering improved electrocatalysts. We herein report a rational design on Ru-RuO 2 hybrid nanoparticles decorating carbon nanotubes composites electrocatalysts (Ru-RuO 2 /CNT), which shows impressively high activity toward hydrogen/oxygen evolution reaction (HER/OER) in all pH aqueous electrolytes. The Ru-RuO 2 /CNT, as an OER catalyst, requires ultralow overpotentials of 0.18 V, 0.27 V and 0.21 V to drive the current density of 10 mA cm−2 in acidic, neutral and alkaline media, respectively. Meanwhile, the catalyst also exhibits superior HER activity with the current density of 10 mA cm−2 at −0.063 V, −0.048 V and −0.012 V in acidic, neutral and alkaline media, respectively. Systematic characterizations and comprehensive electrochemical studies coupling with theoretical calculations verify that Ru favorably works with RuO 2 and CNT to synergistically contribute such highly desirable electrocatalytic activity. The bifunctional catalytic properties, in conjunction with its pH-universal compatibility, inspire us to an asymmetric-electrolyte electrolyzer was set up, which can harvest the electrochemical neutralization energy with implementing electrolysis H 2 generation with a current density of 10 mA cm−2 at an applied voltage of 0.73 V. The as-developed asymmetric-electrolyte electrolyzer, by coupling high-activity but not too expensive electrocatalysts with optimizing the catalytic efficiency in their favorable electrolyte, potentially provides an environmental-friend and energy-saving avenue for the future electrolysis H 2 generation. Image 1 • Bifunctional electrocatalysts for All-pH-electrolyte HER and OER. • High catalytic activity, good durability, and low cost. • Electrochemical neutralization energy was harvested for assisting electrolysis H 2 generation. • Water electrolysis in an asymmetric-electrolyte electrolyzer was implemented within 0.73 V. [ABSTRACT FROM AUTHOR]

Abstract We here report the fabrication of a core-shell WO 3 @ZnIn 2 S 4 heterostructure by an interfacial seeding growth strategy, which is implemented by direct growth of ZnIn 2 S 4 nanosheets on the surface of WO 3 nanorods with forming a strong electronic interaction between two semiconductors that are beneficial for promoting the interfacial charge transfer. Systematic studies demonstrate that the WO 3 @ZnIn 2 S 4 nanohybrids hold superior performance for photocatalytic hydrogen generation under visible light irradiation with a production rate of 3900 μmol g−1 h−1. This work provides an effective approach to construct the direct Z-scheme photocatalytic systems for efficient photocatalytic hydrogen evolution, which would be significant for the design of more direct Z-scheme system for various photocatalytic applications. [ABSTRACT FROM AUTHOR]

Exploring high-activity electrocatalyst for oxygen reduction reaction (ORR) is of great significance for a variety of renewable energy conversion and storage technologies. Herein, we report a template-free, economic and environment-friendly strategy for scalable synthesis of N-doped hierarchical porous carbon nanosheets (N-HPCNSs) with biomass water lettuces as carbon precursor. The N-HPCNSs were demonstrated to possess three dimensional (3D) hierarchical porous structures with a high surface area and uniform N-doping. Systematic electrochemical study revealed that the N-HPCNSs not only hold numerous active sites but also manifest high intrinsic activity for each of the active sites toward ORR in pH-universal electrolyte of alkali, acid and neutral. With the N-HPCNSs as cathode electrocatalyst, three types of home-made fuel cells were set up that run in alkaline, acidic and neutral medium, i.e. , Zn-air alkaline fuel cell, direct methanol fuel cell, and microbial fuel cell, respectively, further demonstrating its potential to replace the high-cost Pt-based electrocatalysts for practical applications. Owning to the multiple attracting features, including high catalytic activity, good durability, low cost, and scalable production, the as-developed pH-universal N-HPCNS electrocatalysts may open a promising avenue for developing the next-generation cathode electrocatalysts for fuel cells of practical significance. [ABSTRACT FROM AUTHOR]