Stabilization of Ni-containing Keggin-type polyoxometalates with variable oxidation states as novel catalysts for electrochemical water oxidation.

The development of new recyclable and inexpensive electrochemically active species for water oxidation catalysis is the most crucial step for future utilization of renewables. Particularly, transition metal complexes containing internal multiple, cooperative metal centers to couple with redox catalysts in the inorganic Keggin-type polyoxometalate (POM) framework at high potential or under extreme pH conditions would be promising candidates. However, most reported Ni-containing POMs have been highly unstable towards hydrolytic decomposition, which precludes them from application as water oxidation catalysts (WOCs).

Ultra-High Proportion of Grain Boundaries in Zinc Metal Anode Spontaneously Inhibiting Dendrites Growth.

Aqueous Zn-ion batteries are an attractive electrochemical energy storage solution for their budget and safe properties. However, dendrites and uncontrolled side reactions in anodes detract the cycle life and energy density of the batteries. Grain boundaries in metals are generally considered as the source of the above problems but we present a diverse result.

Electric-field-assisted proton coupling enhanced oxygen evolution reaction.

The discovery of Mn-Ca complex in photosystem II stimulates research of manganese-based catalysts for oxygen evolution reaction (OER). However, conventional chemical strategies face challenges in regulating the four electron-proton processes of OER. Herein, we investigate alpha-manganese dioxide (α-MnO) with typical Mn-O-Mn-HO motifs as a model for adjusting proton coupling.

What Makes On-Chip Microdevices Stand Out in Electrocatalysis?

Clean and sustainable energy conversion and storage through electrochemistry shows great promise as an alternative to traditional fuel or fossil-consumption energy systems. With regards to practical and high-efficient electrochemistry application, the rational design of active sites and the accurate description of mechanism remain a challenge. Toward this end, in this Perspective, a unique on-chip micro/nano device coupling nanofabrication and low-dimensional electrochemical materials is presented, in which material structure analysis, field-effect regulation, in situ monitoring, and simulation modeling are highlighted.

Surface passivation for highly active, selective, stable, and scalable CO electroreduction.

Electrochemical conversion of CO to formic acid using Bismuth catalysts is one the most promising pathways for industrialization. However, it is still difficult to achieve high formic acid production at wide voltage intervals and industrial current densities because the Bi catalysts are often poisoned by oxygenated species. Herein, we report a BiS nanowire-ascorbic acid hybrid catalyst that simultaneously improves formic acid selectivity, activity, and stability at high applied voltages.

Serrated lithium fluoride nanofibers-woven interlayer enables uniform lithium deposition for lithium-metal batteries.

The uncontrollable formation of Li dendrites has become the biggest obstacle to the practical application of Li-metal anodes in high-energy rechargeable Li batteries. Herein, a unique LiF interlayer woven by millimeter-level, single-crystal and serrated LiF nanofibers (NFs) was designed to enable dendrite-free and highly efficient Li-metal deposition. This high-conductivity LiF interlayer can increase the Li transference number and induce the formation of 'LiF-NFs-rich' solid-electrolyte interface (SEI).

Composition Engineering of Amorphous Nickel Boride Nanoarchitectures Enabling Highly Efficient Electrosynthesis of Hydrogen Peroxide.

Developing advanced electrocatalysts with exceptional two electron (2e ) selectivity, activity, and stability is crucial for driving the oxygen reduction reaction (ORR) to produce hydrogen peroxide (H O ). Herein, a composition engineering strategy is proposed to flexibly regulate the intrinsic activity of amorphous nickel boride nanoarchitectures for efficient 2e ORR by oriented reduction of Ni with different amounts of BH . Among borides, the amorphous NiB delivers the 2e selectivity close to 99% at 0.

Efficient and stable noble-metal-free catalyst for acidic water oxidation.

Developing non-noble catalysts with superior activity and durability for oxygen evolution reaction (OER) in acidic media is paramount for hydrogen production from water. Still, challenges remain due to the inadequate activity and stability of the OER catalyst. Here, we report a cost-effective and stable manganese oxybromide (MnOBr) catalyst exhibiting an excellent OER activity in acidic electrolytes, with an overpotential of as low as 295 ± 5 mV at a current density of 10 mA cm.

New Insights into Phase-Mechanism Relationship of Mg MnO Nanowires in Aqueous Zinc-Ion Batteries.

In response to the call for safer energy storage systems, rechargeable aqueous manganese-based zinc-ion (Zn-ion) batteries using mild electrolyte have attracted extensive attention. However, the charge-storage mechanism and structure change of manganese-based cathode remain controversial topics. Herein, a systematic study to understand the electrochemical behavior and charge storage mechanism based on a 3 × 3 tunnel-structured Mg MnO as well as the correspondence between different tunnel structures and reaction mechanisms are reported.

Ultra-Fast and In-Depth Reconstruction of Transition Metal Fluorides in Electrocatalytic Hydrogen Evolution Processes.

Hitherto, there are almost no reports on the complete reconstruction in hydrogen evolution reaction (HER). Herein, the authors develop a new type of reconfigurable fluoride (such as CoF ) pre-catalysts, with ultra-fast and in-depth self-reconstruction, substantially promoting HER activity. By experiments and density functional theory (DFT) calculations, the unique surface structure of fluorides, alkaline electrolyte and bias voltage are identified as key factors for complete reconstruction during HER.

Constructing Three-Dimensional Macroporous TiO Microspheres with Enhanced Pseudocapacitive Lithium Storage under Deep Discharging/Charging Conditions.

TiO has been intensively investigated as an anode material for lithium-ion batteries (LIBs) in 1.0-3.0 V ( Li/Li).

Regulating Lattice-Water-Adsorbed Ions to Optimize Intercalation Potential in 3D Prussian Blue Based Multi-Ion Microbattery.

Miniaturized energy storage device (MESD) is the core module in microscale electronic equipment, yet its electrochemical performance is far away from the actual requirements. The extensive research efforts have improved the performance of MESD via the fabrication techniques and material construction, while ignoring the expansion of optimization strategy in the combination of energy storage mechanism. Herein, the Prussian blue/Zn microbattery is reported with the regulation of lattice-water-adsorbed intercalated ion.

In situ monitoring of the electrochemically induced phase transition of thermodynamically metastable 1T-MoS at nanoscale.

1T-MoS2 is widely used in the hydrogen evolution reaction (HER) due to its abundant active sites and good conductivity. However, 1T-MoS2 is thermodynamically metastable due to the distorted crystal structure. Recently, researchers have detected the J1 and A1g Raman peaks after the HER process and confirmed that the 2H-1T phase possesses good stability.

Superior Hydrogen Evolution Reaction Performance in 2H-MoS to that of 1T Phase.

In the hydrogen evolution reaction (HER), energy-level matching is a prerequisite for excellent electrocatalytic activity. Conventional strategies such as chemical doping and the incorporation of defects underscore the complicated process of controlling the doping species and the defect concentration, which obstructs the understanding of the function of band structure in HER catalysis. Accordingly, 2H-MoS and 1T-MoS are used to create electrocatalytic nanodevices to address the function of band structure in HER catalysis.

Langmuir-Blodgett Nanowire Devices for In Situ Probing of Zinc-Ion Batteries.

In situ monitoring the evolution of electrode materials in micro/nano scale is crucial to understand the intrinsic mechanism of rechargeable batteries. Here a novel on-chip Langmuir-Blodgett nanowire (LBNW) microdevice is designed based on aligned and assembled MnO nanowire quasimonolayer films for directly probing Zn-ion batteries (ZIBs) in real-time. With an interdigital device configuration, a splendid Ohmic contact between MnO LBNWs and pyrolytic carbon current collector is demonstrated here, enabling a small polarization voltage.

Co-Electrodeposited porous PEDOT-CNT microelectrodes for integrated micro-supercapacitors with high energy density, high rate capability, and long cycling life.

Recently, conducting polymers (CPs) have gained significant attention for their potential applications in micro-supercapacitors (MSCs). Prior to actualizing this potential, however, several critical issues should be resolved, notably their low cycling stability and comparatively low capacitance and energy density. Concurrently, challenges remain in improving the performance of CPs for use in MSCs in terms of their electrical conductivity, energy density, and cycling stability.

High Energy Density Micro-Supercapacitor Based on a Three-Dimensional Bicontinuous Porous Carbon with Interconnected Hierarchical Pores.

On-chip micro-supercapacitors (MSCs) have attracted great attention recently. However, the performance of MSCs is usually unsatisfactory because of the unreasonable pore structure. The construction of a three-dimensional (3D) interconnected porous carbon-based MSC by controllable activation is proposed.

Oxygen evolution reaction dynamics monitored by an individual nanosheet-based electronic circuit.

The oxygen evolution reaction involves complex interplay among electrolyte, solid catalyst, and gas-phase and liquid-phase reactants and products. Monitoring catalysis interfaces between catalyst and electrolyte can provide valuable insights into catalytic ability. But it is a challenging task due to the additive solid supports in traditional measurement.

Field-Effect Tuned Adsorption Dynamics of VSe Nanosheets for Enhanced Hydrogen Evolution Reaction.

Transition metal dichalcogenides, such as MoS and VSe have emerged as promising catalysts for the hydrogen evolution reaction (HER). Substantial work has been devoted to optimizing the catalytic performance by constructing materials with specific phases and morphologies. However, the optimization of adsorption/desorption process in HER is rare.

Field Effect Enhanced Hydrogen Evolution Reaction of MoS Nanosheets.

Hydrogen evolution reaction performance of MoS can be enhanced through electric-field-facilitated electron transport. The best catalytic performance of a MoS nanosheet can achieve an overpotential of 38 mV (100 mA cm ) at gate voltage of 5 V, the strategy of utilizing the electric field can be used in other semiconductor materials to improve their electrochemical catalysis for future relevant research.

Residential proximity to naturally occurring asbestos and mesothelioma risk in California.

Rationale: Little is known about environmental exposure to low levels of naturally occurring asbestos (NOA) and malignant mesothelioma (MM) risk.

Objectives: To conduct a cancer registry-based case control study of residential proximity to NOA with MM in California.

Methods: Incident MM cases (n = 2,908) aged 35 yr or more, diagnosed between 1988 and 1997, were selected from the California Cancer Registry and frequency matched to control subjects with pancreatic cancer (n = 2,908) by 5-yr age group and sex.