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The in situ Fenton reaction utilizing H2O2 has gained significant attention due to its effectiveness in the oxidation of persistent organic pollutants. In this study, we have successfully developed an efficient 2-electron oxygen reduction reaction (2e− ORR) electrocatalyst, Mn-PDA/CNT-2, which exhibits a high H2O2 selectivity of up to 96% within the potential range of 0.65 to 0.85 V vs. RHE in a 0.1 M KOH solution. Moreover, particular emphasis is given to the preparation of an air diffusion floating electrode (ADFE) by incorporating Mn-PDA/CNT-2 onto carbon felt (CF), which enables oxygen in the air to self-drive into the solid state interface of ADFE for the 2e− ORR in bioelectrochemical systems (BESs). Remarkably, the self-aeration ADFE in microbial electrolysis cells (MECs) achieves an impressive maximum current efficiency of 93% for H2O2 production, and the cumulative production of H2O2 reaches a significant amount of 325.18 mg L−1 within a 24 hour period. Additionally, an in situ bio-electro-Fenton system is employed for the degradation of Rhodamine B (RhB). The self-aeration ADFE-MECs system with a Hydraulic Retention Time (HRT) of 6 h demonstrate an effective RhB (6.5 M, pH ≈ 11) degradation rate nearly 90%, accompanied by reduced toxicity in the resulting degradation products. [ABSTRACT FROM AUTHOR]

High-quality Co2P nanodendrites are one-step prepared using a molten-salt-assisted synthesis method, which avoids the release of highly toxic phosphine and the use of flammable organic phosphorus sources. Electrochemical measurements reveal that Co2P nanodendrites can be used as an efficient electrocatalyst for ammonia (NH3) synthesis from the nitrate reduction reaction (NO3−RR) in a neutral electrolyte. At an applied potential of −0.6 V vs. reversible hydrogen electrode, Co2P nanodendrites can operate stably for 10 continuous cycles, and the average faradaic efficiency and yield rate of ammonia generation are 88.57% and 5.11 mg cm−2 h−1, respectively. Thus, the present results will provide new insights into the synthesis of phosphides and the development of NO3−RR catalysts. [ABSTRACT FROM AUTHOR]

Electrolysis systems constructed by anodic urea oxidation reaction (UOR) and cathodic hydrogen evolution reaction (HER) have received considerable attention in sustainable energy and waste utilization. However, current electrolysis systems are far from the requirement of practical applications due to the limited catalytic activity and stability of the electrodes. Herein, we design a UOR electrode with Co-doped NiMoO4 treated in Ar (NCMO–Ar), which shows superior UOR performance because of the Co doping. On the other hand, the Co-doped NiMoO4 treated in H2 (NCMO–H2) delivers high activity for HER. Moreover, the use of a flow electrolysis cell is demonstrated with continuous injection of urea, which only requires a low operation potential of 1.342 V to reach 10 mA cm−2, and shows no attenuation at a large operation current of 100 mA cm−2 for 200 h. It is believed that this high-performance electrolysis system lays an important foundation in developing a practical electrolyzer for efficient and sustainable hydrogen production coupled with waste organic oxidation. [ABSTRACT FROM AUTHOR]

The fabrication of crystalline COF materials with predictable structures and desirable features is one of the crystal engineering strategic goals. Many synthetic factors play an invisible role in the crystallization of COFs, and the nature of the solvent is one of the most influential. Herein, we synthesized two series of benzothiadiazole-based COFs using three pairs of solvent systems of different polarities to explore the effect on the COF synthesis product crystallization, as well as the photocatalytic performance of H2 evolution under visible light irradiation. The results showed that the crystallinity of the COFs increases with increasing solvent polarity. This work showed that increasing the solvent polarity not only enhanced the crystallinity, but also enhanced the thermal stability and gave highly crystalline COFs with a shorter reaction time (30 min). More interestingly, the amorphous materials generated by the use of less solvent polarity (dioxane) can be transferred into crystalline COFs by increasing the polarity of the solvent with butanol or ethanol. The high crystallinity COFs exhibited excellent hydrogen evolution rates. Therefore, this work demonstrates that the choice of solvent is very important. [ABSTRACT FROM AUTHOR]

Zinc (Zn) ion hybrid capacitors (ZIHCs) are promising energy storage devices with the integrated merits of high-capacity Zn-ion batteries and high-power supercapacitors. Their practical application yet remains a challenge due to the relatively low energy density and poor longevity. Herein, a hierarchical porous carbon sphere (HPCS) co-doped with N, P and S is developed, which is featured with a three-dimensional (3D) porous frame structure to deliver a short mass transfer pathway, fast kinetics and enhanced conductivity. The ZIHCs with HPCS-900 as the cathode material enables a large capacity of 104.7 mA h g−1 and excellent energy/power density of 90.17 W h kg−1/81.2 W kg−1 within the voltage window of 0.1–1.7 V. The HPCS-900-based ZIHCs affords a high stability up to 30 000 cycles with a high capacity retention of 95.24%. The HPCS-900 coupled soft-pack ZIHC device exhibits high capacity, high-rate capability and high stability, indicating the great potential of ZIHCs in practical applications. [ABSTRACT FROM AUTHOR]

The continuously increasing CO2 released from human activities poses a great threat to human survival by fluctuating global climate and disturbing carbon balance among the four reservoirs of the biosphere, earth, air, and water. Converting CO2 to value-added feedstocks via electrocatalysis of the CO2 reduction reaction (CO2RR) has been regarded as one of the most attractive routes to re-balance the carbon cycle, thanks to its multiple advantages of mild operating conditions, easy handling, tunable products and the potential of synergy with the rapidly increasing renewable energy (i.e., solar, wind). Instead of focusing on a special topic of electrocatalysts for the CO2RR that have been extensively reviewed elsewhere, we herein present a rather comprehensive review of the recent research progress, in the view of associated value-added products upon selective electrocatalytic CO2 conversion. We initially provide an overview of the history and the fundamental science regarding the electrocatalytic CO2RR, with a special introduction to the design, preparation, and performance evaluation of electrocatalysts, the factors influencing the CO2RR, and the associated theoretical calculations. Emphasis will then be given to the emerging trends of selective electrocatalytic conversion of CO2 into a variety of value-added products. The structure-performance relationship and mechanism will also be discussed and investigated. The outlooks for CO2 electrocatalysis, including the challenges and opportunities in the development of new electrocatalysts, electrolyzers, the recently rising operando fundamental studies, and the feasibility of industrial applications are finally summarized. [ABSTRACT FROM AUTHOR]

Flexible and wearable sensors have shown great potential in tremendous applications such as human health monitoring, smart robots, and human–machine interfaces, yet the lack of suitable flexible power supply devices remains a great challenge hindering their practical applications. To this end, it is essential to develop novel flexible power supply devices that are highly flexible, lightweight, miniaturized, stable, and adaptable for the integration of a self-powered wearable system. Synthesizing intrinsically flexible materials and providing rigid materials good flexibility by a rational architectural design represent the most straightforward approaches to prepare flexible electrode and electrolyte materials, which lay the foundation for the assembly of flexible power devices. Besides, device configuration design and system integration are also essential steps to pave the way for flexible power devices towards real wearable applications. Herein, the main fabrication strategies including material synthesis, architecture design, device configuration design, and system integration for fabricating flexible power devices are overviewed. In addition, the existing challenges and future directions for the development of flexible power supply devices towards self-powered wearable systems will be discussed. [ABSTRACT FROM AUTHOR]

Aqueous electrochemical devices such as batteries and electrolytic cells have emerged as promising energy storage and conversion systems owing to their environmental friendliness, low cost, and high safety characteristics. However, grand challenges are faced to address some critical issues, including how to enhance the potential window and energy density of electrochemical power devices (e.g. fuel cells, batteries, and supercapacitors), and how to minimize the energy consumption in electrolysis. The use of decoupled acid–base asymmetric electrolytes shows great potential in improving the performance of aqueous devices by electrochemically converting the conventional thermal energy of acid–base neutralization into electricity, i.e., electrochemical neutralization energy (ENE). This review aims to introduce the little-known concept of the ENE, including its development history, thermodynamic fundamentals, operating principles, device configurations, and applications. The recent progress made in ENE-assisted electrochemical energy devices emphasizing fuel cells, batteries, supercapacitors, and electrolytic cells is summarized specifically. Finally, the challenges and future perspectives of ENE associated technology are discussed. It is believed that this tutorial review will give a better understanding of the mechanism and operating principles of the ENE to newcomers, which would shed light on the innovative design and fabrication of ENE-assisted devices and thus pave the way for the development of high-performance aqueous electrochemical energy devices. [ABSTRACT FROM AUTHOR]

Metal ion hybrid capacitors (MIHCs) have been recognized as one of the most promising power sources owing to their combined merits of high energy density in batteries and high power output in supercapacitors. The kinetics mismatch between the capacitor-type cathode and battery-type anode yet must be well addressed before implementing their practical feasibility. Here, we overview the recent progress in sodium and potassium ion hybrid capacitors (SIHCs and PIHCs) and discuss the major challenges and give an outlook on the future directions in this field. The fundamental knowledge and the history will be firstly introduced, and special emphasis is then laid on the development of a variety of electrode materials in recent years. The prospects of future research of MIHCs are finally proposed towards their practical applications. We wish that this feature article can not only educate newcomers starting their reasearch in this field, but also inspire experieced researchers to contribute to the development of high-performance MIHC devices. [ABSTRACT FROM AUTHOR]

NH3 synthesis via the electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions has been regarded as a sustainable strategy for fertilizer production and hydrogen fuel storage and mitigating greenhouse gas emissions. The faradaic efficiency (FE) and reaction rate of the NRR, however, are still low for current electrocatalysts. Herein, we develop a metal-free B, N co-doped porous carbon nanofiber (B/N–CNF) that exhibits superior electrocatalytic performance for the NRR in an alkaline electrolyte with the highest FE of 13.2% at −0.5 V and a NH3 yield rate of 32.5 μg h−1 mgcat.−1 at −0.7 V. Such a high NRR activity of the B/N–CNF is superior to that of N- or B-doped carbon materials in the literature. The experimental results reveal that the B–N bonds play a critical role in the NRR process, in which N atoms promote the electron conductivity and B atoms efficiently enhance the N2 adsorption and charge transfer. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide (CO2) reduction (ECR) represents one of the most promising technologies for CO2 conversion into value-added feedstock from carbon monoxide (CO) to a variety of hydrocarbons. As the raw material for Fischer–Tropsch synthesis, CO is one of the most desirable ECR products and has recently received extensive research attention. Although noble metal materials, such as Au and Ag, show high selectivity towards conversion of CO2 to CO, their relative scarcity and high cost seriously limit their practical commercial application. Nanostructured carbon-based non-precious metal electrocatalysts (Nano-CNMs) are of tremendous interest in the field of ECR catalysis due to their tunable structures and electronic properties. Herein, we present an overview of recent progress in the application of Nano-CNMs, mainly including heteroatom-doped carbon, transition metal–heteroatom co-doped carbon, and carbon-based hybrid materials, with emphasis on electrocatalytic conversion of CO2 to CO. We particularly focus on discussing the structure/composition–performance relationships with regard to the electronic structure, surface properties, doping content, and associated electrocatalytic performance of various Nano-CNMs. We outline the future research directions in the development of high-selectivity ECR electrocatalysts for CO production and the stringent challenges in fundamental research and industrial application. [ABSTRACT FROM AUTHOR]

Sodium dual-ion batteries (SDIBs) have received tremendous research attention due to their multiple advantages of environmental friendliness and high working voltages. However, the development of high-performance SDIBs still remains a daunting challenge, mainly due to the lack of robust anode materials with sufficient interlayer spacing for Na+ insertion/extraction. We here report a solvothermal method for the fabrication of coral-like nanohybrids that are constructed from layer-by-layer stacked nitrogen and sulfur co-doped carbon film modified atomic MoS2 nanosheets (a-MoS2NS@NSCfilm). Comprehensive characterization demonstrates that a-MoS2NS@NSCfilm shows favorable electrochemical and structural properties for sodium ion storage, including significantly improved electrical conductivity and an expanded layer space of 0.95 nm thanks to carbon film modification, which favorably facilitate electron transfer and enhance Na+ diffusion kinetics, thus leading to an impressive capability for fast and high-capacity sodium storage. We further verify the practical application of a-MoS2NS@NSCfilm as an anode for SDIBs by coupling it with an expanded graphite (EG) cathode; this delivers a capacity of 40 mA h g−1 with outstanding cycling stability and an extremely low capacity decay of 0.0056% per cycle after 5000 cycles at 10C. [ABSTRACT FROM AUTHOR]

The development of high-kinetic catalysts for the hydrogen evolution reaction (HER) in a neutral electrolyte is of great importance but unfortunately remains a challenge so far. Herein, we report hybrids with abundant Ru–S–Sb bonds and engineered ultrathin antimonene (Ru–S–Sb/antimonene) as highly kinetic, active, stable electrocatalysts for the HER in an aqueous neutral electrolyte. Experiments and density functional theory (DFT) calculations reveal that Ru–S–Sb bonds coupling with antimonene synergistically work to promote HER activity. The present study brings us one step closer to understand the structure–composition–property relationships and practical electrolytic H2 production. [ABSTRACT FROM AUTHOR]

Transition-metal nitrides have captured extensive attention for battery applications ascribed to their high electrical conductivity and considerable capacity, whilst sluggish kinetics constrains their rate capability and thus limited their practical applications in lithium or sodium ion batteries (LIBs or SIBs). Herein, we report an effective approach to prepare nanohybrids of vanadium nitride quantum dots that were uniformly embedded within porous shells of N-doped carbon hollow spheres (VNQD@NC HSs). These manifest attractive advantages as anodes of LIBs and SIBs with facilitated transfer for both electron and Li+/Na+ and robust structural integrity, primarily benefiting from structural features of interior voids, N-doped carbon matrix, and quantum dot level of VN active material. Accordingly, the VNQD@NC HSs electrode can deliver a reversible capacity of up to 832 mA h g−1 at a current density of 0.1 A g−1 after 200 cycles, along with a high rate performance of 378 mA h g−1 at 6.4 A g−1 for LIBs. And for SIBs, the VNQD@NC HSs also retains a capacity of 361 mA h g−1 at a current density of 0.1 A g−1 after 200 cycles and a reversible capacity of 306 mA h g−1 over 1400 cycles at 1 A g−1. [ABSTRACT FROM AUTHOR]

There remains a grand challenge to develop sustainable and pollution-free energy to replace the current dominant but gradually “depleting” fossil fuels. Electrochemical energy conversion presents a promising “bridge” to mitigate energy shortage issues and minimize the ecological implications by synergy with the ever-increasing sustainable energies (e.g., wind and solar). It thus calls for exploring high-activity, low-cost, and long-durability electrocatalysts to facilitate the electrochemical reactions involved in electrochemical energy conversion systems. This review focuses on summarizing the recent progress in the development of bifunctional electrocatalysts for several important electrochemical redox reactions which are critical to implement conversion between electrical energy and chemical energy, especially for bifunctional electrocatalysts applied in a single electrochemical conversion system, including water electrolyzers with the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), zinc–air batteries with the OER and oxygen reduction reaction (ORR), and fuel cells with small molecule (e.g., glucose, urea, and hydrazine hydrate) oxidation reactions (MOR) and the ORR. Special emphasis has been placed on investigating the progress of electrocatalyst synthesis and strategies for improving the electrocatalytic performance and the associated devices' performance in terms of activity, stability, power density etc. We also put forward the major challenges and prospects in the development of bifunctional electrocatalysts for potential applications in a variety of energy devices. [ABSTRACT FROM AUTHOR]

Sodium-ion hybrid capacitors (SIHCs) have shown great promise in achieving both high energy density and high power density by virtue of synergizing the merits of batteries and capacitors. However, the lack of favorable anode material with superior sodium-ion storage capability is still a major challenge in the development of high-performance SIHCs. Herein, we report the design and synthesis of a promising sodium-ion storage nanohybrid with FeS quantum dots embedded in three-dimensional (3D) inverse opal (IO)-structured N-doped carbon (3D-IO FeS-QDs@NC). By virtue of the robust 3D conductive architecture, the 3D-IO FeS-QDs@NC nanohybrid exhibits favorable features of excellent electron/ion transport kinetics, superior structural stability, as well as impressive sodium-ion storage capability with high specific capacity, outstanding rate capability, and ultra-long cyclic stability. Such highly desirable sodium storage performance inspired us to study their potential application in SHICs by coupling with commercial activated carbon (AC) as a cathode. The as-developed SHICs can deliver a maximum energy density and power output of 151.8 W h kg−1 and 9280 W kg−1, respectively, and an excellent cycling lifespan with 91% capacity retention after 5000 cycles at 1 A g−1, which holds promise for bridging the performance gap between conventional batteries and capacitors. [ABSTRACT FROM AUTHOR]

Although the fundamental processes of electrolytic hydrogen generation are relatively well understood, fundamental studies and explorations of the new concepts and materials for electrolysis are highly desirable to make renewable hydrogen sufficiently cost-competitive. Herein, we report a proof-of-concept for an alkaline–acid-based hydrogen generating hydrazine fuel cell by coupling the hydrazine oxidation reaction (HzOR) at the alkaline anode with the hydrogen evolution reaction (HER) at the acidic cathode. Furthermore, we verified that such a hybrid cell could simultaneously fulfill hydrogen production and electricity generation owing to harvesting of two types of electrochemical energies, i.e., electrochemical energy of the HzOR and the electrochemical neutralization energy. To this end, a bifunctional electrode comprising a three-dimensional nanoporous Ni–Co perselenide nanorod array (NixCo1−xSe) was designed and prepared by a facile two-step synthesis process, involving the initial in situ electroplating on a carbon cloth followed by subsequent selenization. The optimized electrode, i.e., Ni0.5Co0.5Se2, showed high electrocatalytic activity toward HzOR in alkaline electrolyte and HER in acidic medium. The optimized alkaline–acid hydrazine fuel cell, with the Ni0.5Co0.5Se2 electrode as both the cathode and anode, could potentially deliver a power density of 13.3 mW cm−2 at a current density of 54.7 mA cm−2 with good long-term stability and a faradaic efficiency of nearly 100% for hydrogen production. [ABSTRACT FROM AUTHOR]

We report the fabrication of self-supported Cu/Cu2O–CuO/rGO nanowire arrays on commercial porous copper foam, which exhibit excellent activity and durability for electrochemical hydrogen evolution, presenting a small onset potential of 84 mV and a low overpotential of 105 mV at a current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

The heteroporous MoS2/Ni3S2 catalyst exhibits excellent electrocatalytic activity for the overall urea splitting with only a cell voltage of 1.45 V at 20 mA cm−2 in 1 M KOH with 0.33 M urea. This value is the best of all the bifunctional urea splitting electrocatalysts, including Pt, reported to date. [ABSTRACT FROM AUTHOR]

The ability to reduce the energy consumed and the cost in water splitting is crucial for the generation of hydrogen, which can be stored and then oxidized to deliver clean, abundant, and sustainable energy with the regeneration of water. Herein, we report an asymmetric electrolyzer with three-dimensional (3D) Ni2P nanorod networks as bifunctional electrocatalysts for acidic cathode and alkaline anode that are separated by a bipolar membrane; this type of electrolyzer affords us with optimization in decreasing the energy required and maximizing the electrocatalysts: (1) pH gradient between an anolyte and a catholyte separated by a bipolar membrane provides the electrolyzer with additional electrochemical neutralization energy for facilitating water splitting and (2) efficiency of electrocatalysts can be maximized by offsetting the well-known mismatch of optimal conditions for electrocatalysts between the anode (normally alkaline) and the cathode (generally acidic). This unprecedented water electrolysis system can activate water splitting at an applied voltage of around 0.79 V that is significantly lower than the minimum theoretical voltage requirement (1.23 V), reducing electricity energy consumed by more than 35.8%. [ABSTRACT FROM AUTHOR]

An unprecedented asymmetric-electrolyte electrolyzer is proposed using an acidic cathode for the hydrogen evolution reaction (HER) and an alkaline anode for the urea oxidation reaction (UOR), which significantly decreases the electrical energy required for electrolytic hydrogen production. [ABSTRACT FROM AUTHOR]

Two nitrogen-rich porous organic polymers (POPs) were prepared via facile and low-cost Schiff base chemistry with ferrocene (Fc) and melamine/melem as building blocks. Carbonization of these POP precursors results in porous carbon nanohybrids with carbon composites containing crystalline Fe3C/Fe. Characterization based on a variety of techniques demonstrates that the porous carbon nanohybrids feature rich-nitrogen doping, good conductivity and high BET surface area with unique porous structure, endowing them with an excellent catalytic activity toward the oxygen reduction reaction (ORR) in alkaline electrolytes. The catalysts obtained by carbonization at 800 °C (N-Fc-800) exhibit favorable activity with a rather high onset potential and half wave potential of 0.96 and 0.82 V, respectively. Furthermore, a rechargeable zinc-air battery was assembled using the N-Fc-800 as the cathode catalyst. Compared with the commercial Pt/C, the N-Fc-800 based battery displays a considerably high power density of 178 mW cm−2 with a smaller charge–discharge voltage gap of 0.94 V, and holds excellent stability with a less activity decay (1.0%) over long charge–discharge cycles (200 cycles). [ABSTRACT FROM AUTHOR]

Exploring high-performance electrocatalysts is of great importance for developing clean and renewable energy conversion systems such as fuel cells and metal–air batteries. Hybrid nanostructures with transition metal nanoparticles embedded in a carbon matrix exhibit outstanding electrocatalytic activity and have emerged as promising low-cost alternatives to precious metal catalysts for a variety of electrochemical reactions. Herein, we report a convenient synthesis route to prepare a three-dimensional porous nanoarchitecture with Co nanoparticles (Co NPs) inlayed in nitrogen-doped macroporous carbon (Co/N-MC). The hybrids show an outstanding electrocatalytic activity for the oxygen reduction (ORR) and glucose oxidation reaction (GOR) due to the synergistic contribution of the Co NPs and nitrogen doping in macroporous carbon. Benefitting from their outstanding electrocatalytic activity in the ORR and GOR, a home-made glucose fuel cell (GFC) was set up using Co/N-MC as the anode and cathode material, delivering a considerable power density with decent stability. [ABSTRACT FROM AUTHOR]

Herein, we report a reliable method for the synthesis of nanohybrids with interconnected networks of reduced graphene oxide (rGO) enwrapping hollow SnO2 nanospheres (H-SnO2@rGO), which is implemented by an electrostatic assembly process between positively charged hollow SnO2 nanospheres and negatively charged rGO. Systematic characterizations demonstrate that the as-developed H-SnO2@rGO has a unique three-dimensional (3D) nanostructure with favorable features for lithium ions storage, which not only provides robust protection against the aggregation and volume changes of the SnO2 nanospheres, but also ensures high transport kinetics for both electrons and lithium ions. The as-developed H-SnO2@rGO exhibits an outstanding electrochemical performance as an anode material for lithium-ion batteries, showing a high reversible capacity of 1107 mA h g−1 after 100 cycles at a current density of 0.1 A g−1 and maintaining 552 mA h g−1 over 500 cycles at a current density up to 1 A g−1. [ABSTRACT FROM AUTHOR]

High-activity electrocatalysts with robust structure are critical for development of renewable-energy technologies. Herein, a hybrid of cobalt nanoparticles embedded in N-doped carbon nanotubes (Co@NCNT) was fabricated via economically scalable pyrolysis of a mixture of a Co-based metal–organic framework (ZIF-67) and dicyandiamide. The as-synthesized Co@NCNT hybrid was characterized by techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photon spectroscopy (XPS) etc., confirming that it possessed desirable properties of high surface area, robust structure, and good conductivity. A series of electrochemical measurements demonstrated that the Co@NCNT exhibits high activity and excellent durability toward several important electrochemical reactions, including hydrogen evolution reaction (HER) in pH-universal electrolyte, oxygen reduction reaction (ORR) in both acidic and alkaline media, glucose oxidation reaction (GOR), and oxygen evolution reaction (OER) in alkaline medium, mainly as a result of the synergistic effects of unique structure and high surface area of the Co nanoparticles and nitrogen dopant in the nanocomposite. A zinc–air battery with outstanding performance was set up using the Co@NCNT as cathode material, demonstrating its potential applications in energy storage and as a conversion system device. [ABSTRACT FROM AUTHOR]

A facile recipe has been developed to prepare three-dimensional nanoarchitectures of nitrogen-doped graphene loading Co nanoparticle hybrids (Co/NG). The hybrids show an outstanding electrocatalytic activity for glucose oxidation reaction (GOR) and oxygen reduction reaction (ORR), and thus can be used as electrode materials of a nonenzymatic and precious-metal-free glucose fuel cell (GFC). [ABSTRACT FROM AUTHOR]

A mesoporous NiFe-based alloy was synthesized through a hard-template technique and investigated as the electrocatalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Precious metal-free elements, i.e., nitrogen (N), nickel (Ni), and iron (Fe), were merged together through either doping or alloying to form a mesoporous structure supporting NiFe-alloy electrocatalyst (m-NiFe/CNx). The synergetic effects from multiple active sites, in combination with structural merits, endowed the m-NiFe/CNx electrocatalyst with an excellent electrocatalytic activity for both OER and ORR, including high activity, fast kinetics, modest overpotential, and excellent stability. The m-NiFe/CNx also featured a simple and scalable synthesis process with a low cost, which makes it an attractive alternative catalyst to precious metal-based electrocatalysts for OER and ORR. [ABSTRACT FROM AUTHOR]

The hybrid Si film/carbon nanofiber (CNF) as an anode in lithium-ion batteries (LIBs) was synthesized using a two-step chemical vapour deposition (CVD) method. This binder- and conductive additive-free electrode delivered a discharge capacity of 1000 mA h g−1 over 200 cycles. CNFs as a support material were directly grown on a stainless steel foil, while the stress-resilient Si films coated on the CNFs offered high Li storage capacity. [ABSTRACT FROM AUTHOR]

Cost-effective catalysts are the key to the successful deployment of microbial electrolysis cells (MECs) for hydrogen production from organic wastes. Herein, we report a novel catalyst for hydrogen evolution in MECs based on a 3D hybrid of layered MoS2/nitrogen-doped graphene nanosheet aerogels (3D MoS2/N-GAs) that were prepared by a facile hydrothermal approach. A high output current density of 0.36 mA cm -- 2 with a hydrogen production rate of 0.19 m3 H2 m -- 3 d -- 1was achieved for the hybrid at a 0.8 V bias, significantly higher than that of MoS2 nanosheets and N-GAs alone and comparable to that of the Pt/C catalyst when being applied in MECs. The outstanding performance of the hybrid benefits from its 3D conductive networks, porous structure, and strong synergic effects between MoS2 nanosheets and N-GAs, making it a promising catalyst for hydrogen production from wastewater through bio-electrochemical reactions. [ABSTRACT FROM AUTHOR]