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A bifunctional bio-photoelectrochemical cell based on a biotic/abiotic hybrid strategy was fabricated as a “trading” platform for renewable energy conversion and H2O2 output under mild pH conditions.

A wide spectrum of state-of-the-art characterization techniques have been devised to monitor the electrode–electrolyte interface that dictates the performance of electrochemical devices. However, coupling multiple characterization techniques to realize in situ multidimensional analysis of electrochemical interfaces remains a challenge. Herein, we presented a hyphenated differential electrochemical mass spectrometry and attenuated total reflection surface enhanced infrared absorption spectroscopy analytical method via a specially designed electrochemical cell that enables a simultaneous detection of deposited and volatile interface species under electrochemical reaction conditions, especially suitable for non-aqueous, electrolyte-based energy devices. As a proof of concept, we demonstrated the capability of the homemade setup and obtained the valuable reaction mechanisms, by taking the tantalizing reactions in non-aqueous lithium-ion batteries (i.e., oxidation and reduction processes of carbonate-based electrolytes on Li1+xNi0.8Mn0.1Co0.1O2 and graphite surfaces) and lithium-oxygen batteries (i.e., reversibility of the oxygen reaction) as model reactions. Overall, we believe that the coupled and complementary techniques reported here will provide important insights into the interfacial electrochemistry of energy storage materials (i.e., in situ, multi-dimensional information in one single experiment) and generate much interest in the electrochemistry community and beyond.

Mechanism research of nanozymes has always been of great interest since their emergence as outstanding mimics of friable natural enzymes. An important but rarely mentioned issue in mechanism research of nanozymology is the inhibitory effect of nanozymes. And conventional nanozymes with various active sites hinder the mechanism research, while single-atom Fe-N-C nanozymes with similar active sites to natural enzymes exhibit structural advantages. Herein, we synthesized Fe single-atom nanozymes (Fe-SANs) with ultrahigh oxidase-like activity and found that a common analgesic-antipyretic drug 4-acetamidophenol (AMP) had inhibitory effects for the oxidase-like activity of Fe-SANs. We investigated the inhibitory effects in detail and demonstrated that the inhibition type was reversible mixed-inhibition with inhibition constants (

Chronic wound is a common complication for diabetic patients, which entails substantial inconvenience, persistent pain, and significant economic burden to patients. However, current clinical treatments for diabetic chronic wounds remain unsatisfactory. A prolonged but ineffective inflammation phase in chronic wounds is the primary difference between diabetic chronic wounds and normal wounds. Herein, we present an effective antioxidative system (MOF/Gel) for chronic wound healing of diabetic rats through integrating a metal organic framework (MOF) nanozyme with antioxidant enzyme-like activity with a hydrogel (Gel). MOF/Gel can continuously scavenge reactive oxygen species to modulate the oxidative stress microenvironment in diabetic chronic wounds, which leads to a natural transition from the inflammation phase to the proliferation phase. Impressively, the efficacy of one-time-applied MOF/Gel was comparable to that of the human epidermal growth factor Gel, a widely used clinical drug for various wound treatments. Such an effective, safe, and convenient MOF/Gel system can meet complex clinical demands.

Solar-to-fuel conversion followed by secondary utilization in fuel cells provides an appealing approach to alleviating global energy shortages but is largely restricted by the complex design of power systems and the development of functional catalysts. Herein, we presented a biohybrid photoelectrochemical cell (BPEC) to implement sustainable solar-to-fuel-to-electric power conversion in a single compartment, by ingeniously combining reliable photoelectrochemical H

High-entropy-oxides (HEOs), a new class of solids that contain five or more elemental species, have attracted increasing interests owing to their unique structures and fascinating physicochemical properties. However, it is a huge challenge to construct various nanostructured, especially low-dimensional nanostructured HEOs under the high temperature synthetic conditions. Herein, a facile strategy using glucose-urea deep eutectic solvent (DES) as both a solvent and the carbon source of structure-directed template is proposed for the synthesis of various HEOs with two-dimentional (2D) nanonets and one-dimentional (1D) nanowires, including rock-salt (Co, Cu, Mg, Ni, Zn)O, spinel (Co, Cr, Fe, Mn, Ni)3O4, and perovskite La(Co, Cr, Fe, Mn, Ni)O3. The as-prepared HEOs possessed five or more uniformly dispersed metal elements, large specific surface areas (more than 25 m2·g−1), and a pure single-phase structure. In addition, high cooling rate (cooling in air or liq-N2-quenching) was indispensable to obtain a single-phase rock-salt (Co, Cu, Mg, Ni, Zn)O because of phase separation caused by copper. By taking advantage of unique features of HEOs, rock-salt (Co, Cu, Mg, Ni, Zn)O can function as a promising candidate for lithium-ion batteries (LIBs) anode material, which achieved excellent cycling stability. This work provides a feasible synthetic strategy for low-dimensional hierarchical HEOs, which creates new opportunities for the stable HEOs being highly active functional materials.

On-site hydrogen peroxide production through electrocatalytic and photocatalytic oxygen reduction reactions has recently attracted broad research interest. However, practical applications have thus far been plagued by the low activity and the requirement of complex equipment. Here, inspired by the process of biological hydrogen peroxide synthesis catalyzed by enzymes, we report a Pt-Au alloy to mimic the catalytic function of natural formate oxidase for hydrogen peroxide synthesis through aerobic oxidation of formic acid. The mass activity of the Pt-Au alloy is three times higher than that of formate oxidase. Density functional theory calculations revealed that the efficient dehydrogenation of formic acid and the high selectivity of the subsequent reduction of oxygen to hydrogen peroxide account for the high hydrogen peroxide productivity. In addition, the formic acid aqueous solution provides an acidic environment, which is conducive to the utilization of the in situ generated hydrogen peroxide for oxidation reactions, including C-H bond oxidation and sterilization.

The development of simple and rapid toxicity detection methods has important practical significance. In this work, a dual-signal method with colorimetric and electrochemical properties for water toxicity detection was proposed for the first time based on a rapid color reaction between Escherichia coli (E. coli) and p-benzoquinone (BQ). Here, E. coli was used as a biocatalyst and BQ was used as a mediator. An IC50 value of 0.75 mg L-1 for Cu2+ was obtained using a two-step electrochemical detection method. Strikingly, toxicity could also be estimated visually by the naked eye, and the minimum detection limit was 3.2 mg L-1 for Cu2+. The dual-signal toxicity detection method extends the function of BQ, and the result is more reliable than the traditional single-signal method. This simple and rapid toxicity detection method shows certain application prospects.

In this work, a novel, environmentally friendly and simple electrochemical/colorimetric water toxicity biosensor was rationally developed by the continuous release of Fe

Various advanced characterization technologies have been employed to obtain a mechanistic understanding and then to improve the electrochemical performance of the aprotic lithium–oxygen batteries. ...

NH3, derived from electrocatalytic nitrogen reduction reaction (NRR), is promising to satisfy the need of food production and serve as a carbon-free liquid energy carrier in the near future. Yet major challenges remain in enhancing NH3 yield rate and conversion efficiency of available electrocatalysts. This work achieved an ultrahigh electrocatalytic NH3 yield rate on the 0.50Fe-Bi2WO6 catalyst by a facile Fe-doped strategy. Up to 289 µg·h−1·mgcat−1 of NH3 formation rate was obtained at −0.75 V vs. RHE, which was reliably quantized by indophenol blue and 1H NMR methods. The impressive result is an order of magnitude higher than that of the reported Fe- and Bi-based catalysts, even more superior than the result of single atom Ru catalyst. The key of the outstanding NRR behaviors on the 0.50Fe-Bi2WO6 catalyst is the significant hydrogen evolution reaction (HER) suppression and the synergy between Bi and Fe, which can effectively modulate the electron distribution and accelerate the electron transport. This work endows a new insight to further explore the high-performance electrocatalysts toward NRR.

Inspired by the nanointerface design of bio-derived structural materials, we design ductile and damage-tolerant carbon nanotube (CNT) fibers by utilizing conductive ionic silk fibroin (ISF) glue to regulate the CNT interface. The mechanical performance of the resulting CNT-ISF fibers is significantly improved, rendering an optimal combination of strength and toughness. Similar to other biological nanocomposites, the CNT-ISF fibers exhibit remarkable damage tolerance behavior due to confined CNT sliding and shearing during tensile fracture, supported by the synchrotron time-resolved small-angle scattering characterization and molecular dynamics simulations. Furthermore, the CNT-ISF fibers rendered an electric conductivity of 4.4 × 104 S m−1, which is comparable to that of the pristine CNT fibers with the same dimensions. Moreover, the CNT-ISF fibers repeatedly exhibit a linear resistance response to tensile stress, which indicates that, instead of the conventional strain sensors, CNT-ISF fibers can be directly employed in stress sensors. Superior mechanical performance and high conductivity demonstrate the promising potential of CNT-ISF fibers in flexible and wearable devices, such as wearable sensors, smart textiles, artificial muscles and human–machine interfaces.

The development of bifunctional catalysts with a delicate structure, high efficiency, and good durability for the oxygen evolution reaction (ORR) and oxygen evolution reaction (OER) is crucial to renewable Zn-air batteries. In this work, Co0.7Fe0.3 alloy nanoparticles (NPs) confined in N-doped carbon with a yolk-shell structure in multi-beaded fibers were prepared as a bifunctional electrocatalyst. The confinement structure was composed of an N-doped graphitized carbon shell and a core formed by numerous Co0.7Fe0.3 NPs, and was evenly threaded into a one-dimensional fiber. Moreover, this distinctive hierarchical structure featured abundant mesopores, a high BET surface area of 743.8 m2 g-1, good electronic conductivity, and uniformly distributed Co0.7Fe0.3/Co(Fe)-Nx coupling active sites. Therefore, the experimentally optimized Co0.7Fe0.3@NC2:1-800 showed excellent OER performance (overpotential reached 314 mV at 10 mA cm-2) that far exceeded RuO2 (353 mV), and good ORR catalytic performance (half-wave potential of 0.827 V) comparable to Pt/C (0.818 V). Impressively, the Co0.7Fe0.3@NC2:1-800 Zn-air battery delivered a higher open circuit voltage of 1.449 V, large power density of 85.7 mW cm-2, and outstanding charge-discharge cycling stability compared with the commercial RuO2 + 20 wt% Pt/C catalyst. This work provides new ideas for the structural design of electrocatalysts and energy conversion systems.

We developed a novel electrospinning strategy, using choline chloride–lactic acid (ChCl–LA) deep eutectic solvent (DES) as an electrospinning solvent to produce lignin fiber aerogels (LFA). The novel strategy is sustainable and cost-effective because no toxic or flammable volatile organic solvents were used and the precursors and waste were designed to be recycled. The fabricated LFA has the appearance of a piece of cotton, and the specific mass was calculated and found to be as low as 3 mg cm−3 with a porosity of over 99.7%. After stabilization and carbonization at a high temperature, the LFA can transform into lignin-based carbon fiber aerogels (LCFA). The LCFA has a high specific surface area (580 m2 g−1) and conductivity, and can be used as an electrochemical electrode material. We made supercapacitor electrodes using the LCFA, the specific capacitance of which is 155 F g−1, much higher than that of commercial multi-wall carbon nanotubes (39 F g−1) at a current density of 0.5 A g−1. The LCFA also have a high electrochemical cycling stability. For the supercapacitor electrodes, only a 2% decrease was observed after 5000 cycles. Moreover, all waste in this work was recycled and reused five times to achieve electrospinning with almost no waste.

Whether noisy quantum devices without error correction can provide quantum advantage over classical computers is a critical issue of current quantum computation. In this work, the random quantum circuits, which are used as the paradigm model to demonstrate quantum advantage, are simulated with depolarizing noise on experiment relevant two-dimensional architecture. With comprehensive numerical simulation and theoretical analysis, we find that the maximum achievable operator entanglement entropy, which indicates maximal simulation cost, has area law scaling with the system size for constant noise rate. On the other hand, we also find that the maximum achievable operator entanglement entropy has power law scaling with the noise rate for fixed system size, and the volume law scaling can be obtained only if the noise rate decreases when system size increase.

As a kind of protoberberine alkaloid heterocyclic analogues, coralyne (COR) has been reported to exhibit superior antileukemic ability and used as anticancer drug agent. While, the severe hazards and side effects caused by unreasonable use have made its accurate detection more and more important. Although scientists have explored various methods to sense COR and other related targets, a systematical review which could not only elaborate recent developments and analyze current challenges of COR-based biosensors, but also present future perspective has not been reported and is urgently needed. In this review, we attempt to summarize latest advancements in COR-based biosensors in recent decade. Firstly, the operating principles, advantages and disadvantages of various strategies for COR detection (colorimetric, fluorescent, electrochemical and other ones) are comprehensively demonstrated and reviewed. Secondly, COR-assisted biosensors for detection of different non-COR targets (heparin, toxins, nucleic acids and other small molecules) are further discussed. Finally, we analyze current challenges and also suggest potential perspectives for this area.

The general toxicity assays for evaluating the risk of aquatic environment were commonly based on single-species test organism models. Thus, the lack and conflict of the different responses among species had hindered researchers to assess the real toxicity of a target toxicant. Therefore, the difference between the test species and their corresponding methodologies was investigated in this work and three species, Escherichia coli, Saccharomyces cerevisiae and Misgurnus anguillicaudatus (a fish), were chosen as the test organism for typical prokaryotes, eukaryotes, and vertebrates, respectively. More specifically, we investigated (i) the individual and combined toxicity of Cu2+ and Zn2+ by the three test organisms; (ii) the different evaluation manners for the test organisms, including IC50 and toxic unit (TU) model for microorganisms by respiratory toxicity assay and enzyme-substrate assay, while survival time for fish; and (iii) the states of test organism, including suspended and immobilized states for microorganisms. The combined effects, including synergistic (Vt Vp) and additive effects for the three species, were complex as that they were usually dose-dependent and could be changed by the different evaluation manners. The present work was useful for enriching of the associated theory and the insights from this work could open the way for further practical risk assessments.