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Mixed multiple oxidation states CoMoO4 nanowires (electrocatalysts) with tunable intrinsic oxygen vacancies were fabricated. CoMoO4 with proper oxygen vacancy can be employed to construct a Li-air battery with a high capacity and stable cyclability. This is possible because CoMoO4 contains surface oxygen vacancies, which result in the unit of CoMo bond, that is important for electrocatalysts used in Li-air batteries. Both the experimental and theoretical results demonstrate that the surface oxygen vacancies containing CoMoO4 nanowires have a higher electrocatalytic activity. This shows that the highly efficient electrocatalysts used for Li-air batteries were designed to modify the redox properties of the mixed metal oxide in the catalytic active sites. This successful material design led to an improved strategy for high oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities based on the fast formation and extinction of ORR products.

Lithium oxygen (Li-O2) batteries have shown great potential as new energy-storage devices due to the high theoretical energy density. However, there are still substantial problems to be solved before practical application, including large overpotential, low energy efficiency, and poor cycle life. Herein, we have successfully synthesized a RuO2-Co3O4 nanohybrid with a rich oxygen vacancy and large specific surface area. The Li-O2 batteries based on the RuO2-Co3O4 nanohybrid shown obviously reduced overpotential and improved circulatory property, which can cycle stably for more than 100 cycles at a current density of 200 mA g-1. Experimental results and density function theory calculation prove that the introduction of RuO2 can increase oxygen vacancy concentration of Co3O4 and accelerate the charge transfer. Meanwhile, the hollow and porous structure leads to a large specific surface area about 104.5 m2 g-1, exposing more active sites. Due to the synergistic effect, the catalyst of the RuO2-Co3O4 nanohybrid can significantly reduce the adsorption energy of the LiO2 intermediate, thereby reducing the overpotential effectively.

Reasonably regulating electronic coupling to promote charge transfer and exciton separation has been regarded a promising approach in catalysis. The material engineering of van der Waals heterojunction (vdWsH) based on two-dimensional (2D) materials would be a potential way to optimize the as-prepared extrinsic physicochemical characteristics. However, it was still an almost uncultivated land waiting for exploration in catalysis. Herein, we introduced the inert h-boron nitride (h-BN) in non-metal reduced graphene oxide (GN) catalysts and constructed BN-GN vdWsH. The theoretical calculation demonstrated that the h-BN can effectively modify the electronic properties of graphene. With the introduction of h-BN, the BN-GN vdWsH can obviously enhance the catalytic activity of Li-CO2 battery. The existence of BN-GN vdWsH can reduce the overpotential more than 700 mV compared with reduced graphene oxide during the CO2 reduction reaction (CO2RR) and CO2 evolution reaction (CO2ER), and it extended cyclic stability more than three times, which was one of the most outstanding non-metallic catalysts. The reasonable structure design made it work as a high efficient electrocatalyst, which shed light on the development for functional treatment of catalytic materials.

Substrate channeling, where an intermediate in a multistep reaction is directed toward a reaction center rather than freely diffusing, offers several advantages when employed in catalytic cascades. Here we present a fusion enzyme comprised of an alcohol and aldehyde dehydrogenase, that is computationally designed to facilitate electrostatic substrate channeling using a cationic linker bridging the two structures. Rosetta protein folding software was utilized to determine an optimal linker placement, added to the truncated termini of the proteins, which is as close as possible to the active sites of the enzymes without disrupting critical catalytic residues. With improvements in stability, product selectivity (90%), and catalyst turnover frequency, representing 500-fold increased activity compared to the unbound enzymes and nearly 140-fold for a neutral-linked fusion enzyme, this design strategy holds promise for making other multistep catalytic processes more sustainable and efficient.

Nitrogenase is the only biological catalyst that is known to be able to convert nitrogen gas to ammonia. In microorganisms, the MoFe catalytic protein of nitrogenase is reduced by a transient Fe pr...

Due to the limited energy densities, which could be achieved by lithium-ion cells, Li-O2 batteries, which could provide a promising super energy storage medium, attract much attention nowadays. For its high activity, high storage and low cost, Mn-based oxides have shown versatile application in various batteries. To enhance the cyclability of Li-O2 batteries, here, we synthesized a kind of α-MnO2 nanowires as a bifunctional catalyst for Li-O2 batteries. The particular structure of α-MnO2 reduces the mass transfer resistance of the battery, and the MnO2 nanowires were ion exchanged by saturated lithium sulfate solution so as to further improve the performance of the catalyst. The exchanged α-MnO2 catalyst showed a high discharge specific capacity(6243 mA·h/g at a current density of 200 mA/g) and significantly improved the cyclability up to the 55th cycle(200 mA/g with capacity of 1000 mA·h/g). The results show that the Li ion exchange method is a promising strategy for improving the performance of MnO2 catalyst for Li-O2 batteries.

Urea, as a prospective energy source, is rarely utilized for lack of effective catalysts to overcome its sluggish kinetics during its electrolysis. Exploiting low-cost and high-efficiency catalysts to accelerate the urea oxidation reaction (UOR) does make sense as it can relieve not only energy shortage but also the water contamination problems. In this work, the Ni₃S₂ nanosheets grown on the Ni foam with different amounts of Mn²⁺ doping were developed as useful electrocatalysts toward UOR. The experimental and computational methods were performed to explore the properties of obtained samples. We found that the doping of Mn²⁺ could distinctly regulate the charge distribution of Ni₃S₂ by which the performance was observably optimized. We also compared the behaviors of obtained catalysts with various dopant concentrations of Mn²⁺. Especially, Ni₃S₂ grown on the Ni foam with the addition of 0.2 mmol of Mn²⁺ exhibits splendid properties with a lower potential and superior longevity, which can achieve a current density of 100 mA cm–² at a voltage of only 1.397 V (vs reversible hydrogen electrode) in 1.0 M KOH containing 0.5 M urea solution, indicating that our findings can serve as promising electrocatalysts for urea electrolysis.

NiFe layered double hydroxides (LDHs) have been denoted as benchmark non-noble-metal electrocatalysts for the oxygen evolution reaction (OER). However, for laminates of NiFe LDHs, the edge sites are active, but the basal plane is inert, leading to underutilization as catalysts for the OER. Herein, for the first time, light and electron-deficient Li ions are intercalated into the basal plane of NiFe LDHs. The results of theoretical calculations and experiments both showed that electrons would be transferred from near Ni2+ to the surroundings of Li+ , resulting in electron-deficient properties of the Ni sites, which would function as "electron-hungry" sites, to enhance surface adsorption of electron-rich oxygen-containing groups, which would enhance the effective activity for the OER. As demonstrated by the catalytic performance, the Li-NiFe LDH electrodes showed an ultralow overpotential of only 298 mV at 50 mA cm-2 , which was lower than that of 347 mV for initial NiFe LDHs and lower than that of 373 mV for RuO2 . Reasonable intercalation adjustment effectively activates laminated Ni2+ sites and constructs the electron-deficient structure to enhance its electrocatalytic activity, which sheds light on the functional treatment of catalytic materials.

Two obstacles limit the application of oxidoreductase-based asymmetric synthesis. One is the consumption of high stoichiometric amounts of reduced cofactor. The other is the low solubility of organic substrates, intermediates, and products in the aqueous phase. In order to address these two obstacles to oxidoreductase-based asymmetric synthesis, a biphasic bioelectrocatalytic system was constructed and applied. In this study, the preparation of chiral β-hydroxy nitriles catalyzed by alcohol dehydrogenase (AdhS) and halohydrin dehalogenase (HHDH) was investigated as a model bioelectrosynthesis, since they are high-value intermediates in statin synthesis. Diaphorase (DH) was immobilized by a cobaltocene-modified poly(allylamine) redox polymer on the electrode surface (DH/Cc-PAA bioelectrode) to achieve effective bioelectrocatalytic NADH regeneration. Since AdhS is a NAD-dependent dehydrogenase, the diaphorase-modified biocathode was used to regenerate NADH to support the conversion from ethyl 4-chloroacetoacetate (COBE) to ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) catalyzed by AdhS. The addition of methyl tert-butyl ether (MTBE) as an organic phase not only increased the uploading of COBE but also prevented the spontaneous hydrolysis of COBE, extended the lifetime of DH/Cc-PAA bioelectrode, and increased the Faradaic efficiency and the concentration of generated (R)-ethyl-4-cyano-3-hydroxybutyrate ((R)-CHCN). After 10 h of reaction, the highest concentration of (R)-CHCN in the biphasic bioelectrocatalytic system was 25.5 mM with 81.2% enantiomeric excess (eep). The conversion ratio of COBE achieved 85%, which was 8.8 times higher than that achieved with the single-phase system. Besides COBE, two other substrates with aromatic ring structures were also used in this biphasic bioelectrocatalytic system to prepare the corresponding chiral β-hydroxy nitriles. The results indicate that the biphasic bioelectrocatalytic system has the potential to produce a variety of β-hydroxy nitriles with different structures.

Aliphatic synthetic intermediates with high added value are generally produced from alkane sources (e.g., petroleum) by inert carbon-hydrogen (C-H) bond activation using classical chemical methods (i.e. high temperature, rare metals). As an alternative approach for these reactions, alkane monooxygenase from Pseudomonas putida (alkB) is able to catalyze the difficult terminal oxyfunctionalization of alkanes selectively and under mild conditions. Herein, we report an electrosynthetic system using an alkB biocathode which produces alcohols, epoxides, and sulfoxides through bioelectrochemical hydroxylation, epoxidation, sulfoxidation, and demethylation. The capacity of the alkB binding pocket to protect internal functional groups is also demonstrated. By coupling our alkB biocathode with a hydrogenase bioanode and using H2 as a clean fuel source, we have developed and characterized a series of enzymatic fuel cells capable of oxyfunctionalization while simultaneously producing electricity.

Aqueous-phase oxygen evolution reaction (OER) is the bottleneck of water splitting. The formation of the O-O bond involves the generation of paramagnetic oxygen molecules from the diamagnetic hydroxides. The spin configurations might play an important role in aqueous-phase molecular electrocatalysis. However, spintronic electrocatalysis is almost an uncultivated land for the exploration of the oxygen molecular catalysis process. Herein, we present a novel magnetic Fe

Regulating the structure and morphology of discharge product is one of the key points for developing high performance Li-O

Introduction: Familial amyloid polyneuropathy is currently prevalent worldwide as the transthyretin (TTR) Val30Met mutation, and there are other types of mutations. The purpose of this study was to understand the clinical manifestations, electrophysiological characteristics, and outcomes of hormone-related therapy in patients with the TTR Val30Leu mutation in China. Methods: Clinical data were collected from 9 members of a family with the TTR Val30Leu mutation in China, and blood samples of 7 members of the family were sequenced. The electrophysiological examinations of 4 of them were collected and analysed. Results: A total of 7 people had the TTR gene c.148G>T missense mutation and the TTR protein Val30Leu mutation in this family, and the positive members all had similar symptoms, such as limb paraesthesia and gastrointestinal symptoms. In addition, electrophysiological examination showed abnormal nerve conduction velocity in all 4 patients. Conclusions: The clinical manifestations of this mutation involve mainly limb sensory or motor disorders or gastrointestinal symptoms or both, and the electrophysiological examination shows neurogenic damage.

Two-dimensional MXene with high conductivity has metastable Ti atoms and inert functional groups on the surface, greatly limiting application in surface-related electrocatalytic reactions. A surface-functionalized nitrogen-doped two-dimensional TiO

Due to the advantages of rich resources, low cost, high energy conversion efficiency, long cycle life, and low maintenance fee, sodium–ion batteries have been regarded as a promising energy storage technology. However, their relatively low energy density compared with the commercialized lithium–ion batteries still impedes their application for power systems. Anode–free rechargeable sodium–metal batteries (AFSMBs) pose a solution to boost energy density and tackle the safety problems of metal batteries. At present, researchers still lack a comprehensive understanding of the anode-free cells in terms of electrolytes, solid–electrolyte interphase (SEI), and current collectors. This review is devoted to the field of AFSMBs, and outlines the breakthroughs that have been accomplished along with our perspective on the direction of future development for AFSMBs and the areas that warrant further investigation.

BackgroundTo analyze the relationship between apolipoprotein E(APOE) (including the SNPs rs429358 and rs7412) gene and cerebral infarction(CI) in Northern Chinese Han population.Methods457 CI patients and 416 controls (without CI) in Chinese Han population were recruited for our study to test the SNPs by polymerase chain reaction (PCR)-fluorescence probe technique.ResultsThe distribution of APOE genotypes were in Hardy-Weinberg equilibrium, and the frequencies of ɛ4 allele orɛ4 containing were significantdifference between CI and control groups. Compared to ε2 or ε3 carriers, ε4 carriers had a high level of total cholesterol (TC) and low-density lipoprotein cholesterol(LDL-C) and high presenceof dyslipidemia in recruited peoples. And we found APOE ε4 allele was associated with an increased risk of dyslipidemia in the control and CI groups (OR = 2.232, 95% CI= 1.143-4.361, PP=0.019). However, further logistic regression showed that ɛ4 allele or carriers were not the independent risk factors of CI (OR = 2.232, 95% CI= 1.143-4.361, P=0.144; OR = 3.442, 95% CI= 1.885-6.284, P=0.162).ConclusionAPOE ε4 allele was associated with an increased risk of dyslipidemia (OR = 2.232, 95% CI= 1.143-4.361; OR = 3.442, 95% CI= 1.885-6.284), but ɛ4 allele or carriers were not the independent risk factors of CI in Northern Chinese Han population (OR = 2.232, 95% CI= 1.143-4.361, P=0.144; OR = 3.442, 95% CI= 1.885-6.284, P=0.162).

We demonstrate a new material by intercalating Mo

Lithium oxygen (Li-O

The topological structure of carbon materials for lithium storage performance is an active issue in energy resources. However, the low specific capacity of carbon materials limits their application in the rapidly developing market, although they have the highest marginal value. Herein, we develop a facile method for scaled-up production of materials with atomically dispersed metal sites anchored on nitrogen-enriched carbon nanosheets (M–N–C), including nickel, iron and manganese metal sites. This is the first time that low-cost atomically dispersed M–N–C has been used to enhance Li storage performance. The anchoring of the atomically dispersed metal sites effectively improves the extent of carbonization and optimizes the electronic structure, which enhances the conductivity and accelerates the adsorption kinetics for Li+; this results in high capacity and superior rate performance. In the case of Mn–N–C, it presents an ultrahigh specific capacity of 500 mA h g−1 at 1 A g−1 after 1000 cycles. The atomically dispersed materials also demonstrate satisfactory rate performance, with an extremely high specific capacity of 328 mA h g−1 at 10 A g−1; this is greatly superior to that of N-doped carbon nanosheets (

The new material Polypyrrole-Mo3S13 (abbr. Mo3S13-Ppy) is a new material prepared by ion-exchange between Ppy-NO3 and (NH4)2Mo3S13. The Mo3S13-Ppy was designed to exhibit strong selectivity for Ag+ and highly toxic Hg2+ in mixtures with other ions. It displays an apparent selectivity ranking of Hg2+ > Ag+ ≥ Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Pb2+. The strong affinity of Mo3S13-Ppy for Ag+ and Hg2+ was confirmed with extremely high distribution coefficients (Kd) (∼107 mL/g) and remarkable removal efficiencies (>99.99%), resulting in

Two-dimensional MXene, a significant member of the two-dimensional family, has attracted much interest in physics, energy evolution, environmental science, and nanomedicine. However, the acute toxi...

We develop a facile method to prepare a hierarchical mesoporous nanocomposite of manganese carbodiimide nanoparticles modified with N-doping carbon materials (MnNCN/NC). The nanocomposite is endowe...

Atmospheric CO2 is a cheap and abundant source of carbon for synthetic applications. However, the stability of CO2 makes its conversion to other carbon compounds difficult and has prompted the extensive development of CO2 reduction catalysts. Bioelectrocatalysts are generally more selective, highly efficient, can operate under mild conditions, and use electricity as the sole reducing agent. Improving the communication between an electrode and a bioelectrocatalyst remains a significant area of development. Through the examples of CO2 reduction catalyzed by electroactive enzymes and whole cells, recent advancements in this area are compared and contrasted.

Nanocomposites of CoNi alloy nanoparticles loaded on Ketjenblack carbon (CoNi/KB) are successfully prepared through one-pot thermal decomposition of organic precursor solution. It can be proved, through a serious of characterization methods, that the introduction of porous carbon nanospheres with high specific surface area effectively prevents the serious agglomeration and oxidation of alloy nanoparticles. Highly dispersed CoNi alloy nanoparticles are evenly distributed on the surface of carbon nanospheres with a size of about ca. 5 nm. The CoNi/carbon nanosphere composites exhibit excellent electromagnetic wave absorbability when the doping mass is merely 15 wt% with the minimum reflection loss of −39.5 dB at 12.4 GHz and the effective absorption bandwidth (

The design of low-cost yet high-efficiency electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) over a wide pH range is highly challenging. We now report a hierarchical co-assembly of interacting MoS2 and Co9S8 nanosheets attached on Ni3S2 nanorod arrays which are supported on nickel foam (NF). This tiered structure endows high performance toward HER and OER over a very broad pH range. By adjusting the molar ratio of the Co:Mo precursors, we have created CoMoNiS-NF- xy composites ( x: y means Co:Mo molar ratios ranging from 5:1 to 1:3) with controllable morphology and composition. The three-dimensional composites have an abundance of active sites capable of universal pH catalytic HER and OER activity. The CoMoNiS-NF-31 demonstrates the best electrocatalytic activity, giving ultralow overpotentials (113, 103, and 117 mV for HER and 166, 228, and 405 mV for OER) to achieve a current density of 10 mA cm-2 in alkaline, acidic, and neutral electrolytes, respectively. It also shows a remarkable balance between electrocatalytic activity and stability. Based on the distinguished catalytic performance of CoMoNiS-NF-31 toward HER and OER, we demonstrate a two-electrode electrolyzer performing water electrolysis over a wide pH range, with low cell voltages of 1.54, 1.45, and 1.80 V at 10 mA cm-2 in alkaline, acidic, and neutral media, respectively. First-principles calculations suggest that the high OER activity arises from electron transfer from Co9S8 to MoS2 at the interface, which alters the binding energies of adsorbed species and decreases overpotentials. Our results demonstrate that hierarchical metal sulfides can serve as highly efficient all-pH (pH = 0-14) electrocatalysts for overall water splitting.

Redox polymers have been an expanding research area over the last 30 years. The design of redox polymers for mediated bioelectrocatalysis revolutionized glucose biosensors in the early 1990s. These concepts were then applied to biofuel cells in the 2000s, but it was not until recently that researchers further translated these concepts to the fields of electrosynthesis, supercapacitors, and redox flow batteries. This review will give a short background to the early work in the field but will primarily discuss the recent applications of the electrosynthesis, supercapacitors, and redox flow batteries.

Li–oxygen batteries (LOBs) have drawn widespread attention in the past decades. Herein, bifunctional hybrid catalysts based on perovskite La0.5Sr0.5CoO3−δ with Ti3C2Tx MXene nanosheets have been pr...

Similar as temperature, air humidity may affect people's thermal comfort and humidity adaptation may happen when people changing their living conditions. To provide evidence on both effect from humidity on people's thermal comfort and their humidity adaptation, a comparative study has been conducted in a controlled climate chamber. During the experiment, the air temperature was set as 25 °C and 28 °C respectively and the relative humidity was changing between 20% and 90%. There were twenty four participants involved in this experiment, with half living in High Humidity (HH) regions of China, such as Chongqing, for over 20 years, and another half recently moved to Chongqing from Low Humidity (LH) regions in northwestern China. During the experiment, mean skin temperature was measured as an objective important parameter and subjective questionnaires were used to subjectively collect people's sensations with respect to heat, humidity and sweating. The data collected demonstrated that people living in HH regions showed a better adaptive ability to humidity changes than those came from LH regions. Climate adaptation also reduced the sensitivity of HH subjects' thermal responses. When air humidity was over 70%, subjects started to show stronger thermal responses. Based on these results, an upper limit of humidity of 17 g/kg has been proposed for Chongqing, China. The results from this study will help to broaden the adaptive thermal comfort theory and can provide important references regarding to humidity control for buildings.

The development of highly effective, universal, and economical electrocatalysts for hydrogen evolution reaction (HER) via structure modulations remains a great challenge. Herein, we propose a novel solidoid nitridation reduction method to synthesize α-MoC1–x quantum dots encapsulated in nitrogen-doped carbon (α-MoC1–x/NC) with a shape like “frog eggs”. Carbon nitride was first prepared by pyrolysis of urea and then mixed with ammonium molybdate tetrahydrate under a temperature-programmed reduction. With the assistance of nitrogen release during thermal treatment, N doping and an ultrathin porous structure were obtained. Benefiting from the strong interaction of α-MoC1–x quantum dots and nitrogen-doped carbon, the α-MoC1–x/NC delivered an outstanding performance toward HER at all pH values. Here, 118 mV, a lower overpotential, is needed to reach 10 mA cm–2 in alkaline solution, and the current density of α-MoC1–x grew much faster than the commercial Pt/C with increased potential. And, this can keep steadil...

The development of novel and highly efficient bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is an ongoing challenge. The Cr3+ cati...

Ultrathin two-dimensional metal–organic frameworks (2D MOFs) have the potential to improve the performance of Li–O2 batteries with high O2 accessibility, open catalytic active sites, and large surface areas. To obtain highly efficient cathode catalysts for aprotic Li–O2 batteries, a facile ultrasonicated method has been developed to synthesize three kinds of 2D MOFs (2D Co-MOF, Ni-MOF, and Mn-MOF). Contributing from the inherent open active sites of the Mn–O framework, the discharge specific capacity of 9464 mAh g–1 is achieved with the 2D Mn-MOF cathode, higher than those of the 2D Co-MOF and Ni-MOF cathodes. During the cycling test, the 2D Mn-MOF cathode stably operates more than 200 cycles at 100 mA g–1 with a curtailed discharge capacity of 1000 mAh g–1, quite longer than those of others. According to further electrochemical analysis, we observe that the 2D Mn-MOF outperforms 2D Ni-MOF and Co-MOF due to a superior oxygen reduction reactions and oxygen evolution reactions activity, in particular, the e...