Seawater electrolysis using renewable electricity offers an attractive route to sustainable hydrogen production, but the sluggish electrode kinetics and poor durability are two major challenges. We report a molybdenum nitride (MoN) catalyst for the hydrogen evolution reaction with activity comparable to commercial platinum on carbon (Pt/C) catalyst in natural seawater. The catalyst operates more than 1000 hours of continuous testing at 100 mA cm without degradation, whereas massive precipitate (mainly magnesium hydroxide) forms on the Pt/C counterpart after 36 hours of operation at 10 mA cm.
View Article and Find Full Text PDFWith the rapid development of anion exchange membrane technology and the availability of high-performance non-noble metal cathode catalysts in alkaline media, the commercialization of anion exchange membrane fuel cells has become feasible. Currently, anode materials for alkaline anion-exchange membrane fuel cells still rely on platinum-based catalysts, posing a challenge to the development of efficient low-Pt or Pt-free catalysts. Low-cost ruthenium-based anodes are being considered as alternatives to platinum.
View Article and Find Full Text PDFFinding highly efficient hydrogen evolution reaction (HER) catalysts is pertinent to the ultimate goal of transformation into a net-zero carbon emission society. The design principles for such HER catalysts lie in the well-known structure-property relationship, which guides the synthesis procedure that creates catalyst with target properties such as catalytic activity. Here we report a general strategy to synthesize 10 kinds of single-atom-doped CoSe-DETA (DETA = diethylenetriamine) nanobelts.
View Article and Find Full Text PDFElectrochemical generation of hydrogen peroxide (H O ) by two-electron oxygen reduction offers a green method to mitigate the current dependence on the energy-intensive anthraquinone process, promising its on-site applications. Unfortunately, in alkaline environments, H O is not stable and undergoes rapid decomposition. Making H O in acidic electrolytes can prevent its decomposition, but choices of active, stable, and selective electrocatalysts are significantly limited.
View Article and Find Full Text PDFBackground: The latest incidence and disability-adjusted life-years (DALYs) of major bacterial skin diseases (BSD) and their relationship with socioeconomic are not readily available.
Objective: Describe the global age-standardized incidence and DALYs rates of BSD and analyze their relationship with socioeconomic.
Methods: All data were obtained from Global Burden of Disease (GBD) 2019 database.
Electrosynthesis of hydrogen peroxide (H O ) in the acidic environment could largely prevent its decomposition to water, but efficient catalysts that constitute entirely earth-abundant elements are lacking. Here we report the experimental demonstration of narrowing the interlayer gap of metallic cobalt diselenide (CoSe ), which creates high-performance catalyst to selectively drive two-electron oxygen reduction toward H O in an acidic electrolyte. The enhancement of the interlayer coupling between CoSe atomic layers offers a favorable surface electronic structure that weakens the critical *OOH adsorption, promoting the energetics for H O production.
View Article and Find Full Text PDFAlthough the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag Se on CoSe nanobelts relied on diffusion-driven instability. The resultant Turing-type Ag Se-CoSe material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.
View Article and Find Full Text PDFSelective and efficient catalytic conversion of carbon dioxide (CO) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO reduction to oxygenates and hydrocarbons (e.g.
View Article and Find Full Text PDFA considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO to CO or other intermediates, which often requires precious-metal catalysts, high overpotentials, and/or electrolyte additives (e.g., ionic liquids).
View Article and Find Full Text PDFMany platinum group metal-free inorganic catalysts have demonstrated high intrinsic activity for diverse important electrode reactions, but their practical use often suffers from undesirable structural degradation and hence poor stability, especially in acidic media. We report here an alkali-heating synthesis to achieve phase-mixed cobalt diselenide material with nearly homogeneous distribution of cubic and orthorhombic phases. Using water electroreduction as a model reaction, we observe that the phase-mixed cobalt diselenide reaches the current density of 10 milliamperes per square centimeter at overpotential of mere 124 millivolts in acidic electrolyte.
View Article and Find Full Text PDFMaterial interfaces permit electron transfer that modulates the electronic structure and surface properties of catalysts, leading to radically enhanced rates for many important reactions. Unlike conventional thoughts, the nanoscale interfacial interactions have been recently envisioned to be able to affect the reactivity of catalysts far from the interface. However, demonstration of such unlocalized alterations in existing interfacial materials is rare, impeding the development of new catalysts.
View Article and Find Full Text PDFBio-inspired synthesis of functional materials with highly ordered structure and tunable properties is of particular interest, but efficient approaches that allow the access of these materials are still limited. A method has been developed for the preparation of hematite particles by using xonotlite nanowires (XNWs) as growth modifiers. The concentration of the XNWs has a profound effect on the final morphology of the products, whereas the concentration of the iron(III) ions can control the size of the hematite particles.
View Article and Find Full Text PDFThe design of highly efficient non-noble-metal electrocatalysts for large-scale hydrogen production remains an ongoing challenge. We report here a NiP nanoarray catalyst grown on a commercial Ni foam substrate, which demonstrates an outstanding electrocatalytic activity and stability in basic electrolyte. The high catalytic activity can be attributed to the favorable electron transfer, superior intrinsic activity, and the intimate connection between the nanoarrays and their substrate.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2018
Transition-metal phosphides have stimulated great interest as catalysts to drive the hydrogen evolution reaction (HER), but their use as bifunctional catalytic electrodes that enable efficient neutral-pH water splitting has rarely been achieved. Herein, we report the synthesis of ternary Ni Co P porous nanosheets onto conductive carbon fiber paper that can efficiently and robustly catalyze both the HER and water oxidation in 1 m phosphate buffer (PBS; pH 7) electrolyte under ambient conditions. A water electrolysis cell comprising the Ni Co P electrodes demonstrates remarkable activity and stability for the electrochemical splitting of neutral-pH water.
View Article and Find Full Text PDFTransition metal dichalcogenide materials have been explored extensively as catalysts to negotiate the hydrogen evolution reaction, but they often run at a large excess thermodynamic cost. Although activating strategies, such as defects and composition engineering, have led to remarkable activity gains, there remains the requirement for better performance that aims for real device applications. We report here a phosphorus-doping-induced phase transition from cubic to orthorhombic phases in CoSe.
View Article and Find Full Text PDFUltrathin nanostructures are attractive for diverse applications owing to their unique properties compared to their bulk materials. Transition-metal chalcogenides are promising electrocatalysts, yet it remains difficult to make ultrathin structures (sub-2 nm), and the realization of their chemical doping is even more challenging. Herein we describe a soft-template mediated colloidal synthesis of Fe-doped NiSe ultrathin nanowires (UNWs) with diameter down to 1.
View Article and Find Full Text PDFSince being proposed by John Bockris in 1970, hydrogen economy has emerged as a very promising alternative to the current hydrocarbon economy. Access to reliable and affordable hydrogen economy, however, requires cost-effective and highly efficient electrocatalytic materials that replace noble metals (e.g.
View Article and Find Full Text PDFCobalt-based nanomaterials have been intensively explored as promising noble-metal-free oxygen evolution reaction (OER) electrocatalysts. Herein, we report phase-selective syntheses of novel hierarchical CoTe and CoTe nanofleeces for efficient OER catalysts. The CoTe nanofleeces exhibited excellent electrocatalytic activity and stablity for OER in alkaline media.
View Article and Find Full Text PDFThe development of active, stable and low-cost electrocatalysts towards both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) for overall water splitting remains a big challenge. Herein, we report a new porous carbon-supported Ni/MoC (Ni/MoC-PC) composite catalyst derived by thermal treatment of nickel molybdate nanorods coated with polydopamine, which efficiently and robustly catalyses the HER and OER with striking kinetic metrics in alkaline electrolyte. The catalyst affords low onset potentials of -60 mV for the HER and 270 mV for the OER, as well as small overpotentials of 179 mV for the HER and 368 mV for the OER at a current density of 10 mA cm.
View Article and Find Full Text PDFLow-density compressible materials enable various applications but are often hindered by structure-derived fatigue failure, weak elasticity with slow recovery speed and large energy dissipation. Here we demonstrate a carbon material with microstructure-derived super-elasticity and high fatigue resistance achieved by designing a hierarchical lamellar architecture composed of thousands of microscale arches that serve as elastic units. The obtained monolithic carbon material can rebound a steel ball in spring-like fashion with fast recovery speed (∼580 mm s), and demonstrates complete recovery and small energy dissipation (∼0.
View Article and Find Full Text PDFDesign and fabrication of low-cost, highly efficient and robust three-dimensional (3D) hierarchical structure materials for electrochemical reduction of water to make molecular hydrogen is of paramount importance for real water splitting applications. Herein, a 3D hydrogen evolution cathode constructed by growing of cobalt diselenide nanobelts on the surface of commercial carbon fiber felt shows exceptionally high catalytic activity with 141 mV overpotential to afford a current density of 10 mA cm, and a high exchange current density of 5.9 × 10 mA cm.
View Article and Find Full Text PDFThe electroreduction of water for sustainable hydrogen production is a critical component of several developing clean-energy technologies, such as water splitting and fuel cells. However, finding a cheap and efficient alternative catalyst to replace currently used platinum-based catalysts is still a prerequisite for the commercialization of these technologies. Here we report a robust and highly active catalyst for hydrogen evolution reaction that is constructed by in situ growth of molybdenum disulfide on the surface of cobalt diselenide.
View Article and Find Full Text PDFResorcinol-formaldehyde (RF) and graphene oxide (GO) aerogels have found a variety of applications owing to their excellent properties and remarkable flexibility. However, the macroscopic and controllable synthesis of their composite gels is still a great challenge. By using GO sheets as template skeletons and metal ions (Co(2+), Ni(2+), or Ca(2+)) as catalysts and linkers, the first low-temperature scalable strategy for the synthesis of a new kind of RF-GO composite gel with tunable densities and mechanical properties was developed.
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