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Zinc–iodine batteries are one of the most intriguing types of batteries that offer high energy density and low toxicity. However, the low intrinsic conductivity of iodine, together with high polyiodide solubility in aqueous electrolytes limits the development of high-areal-capacity zinc–iodine batteries with high stability, especially at low current densities. Herein, we proposed a hydrophobic polyiodide ionic liquid as a zinc-ion battery cathode, which successfully activates the iodine redox process by offering 4 orders of magnitude higher intrinsic electrical conductivity and remarkably lower solubility that suppressed the polyiodide shuttle in a dual-plating zinc–iodine cell. By the molecular engineering of the chemical structure of the polyiodide ionic liquid, the electronic conductivity can reach 3.4 × 10–3S cm–1with a high Coulombic efficiency of 98.2%. The areal capacity of the zinc–iodine battery can achieve 5.04 mAh cm–2and stably operate at 3.12 mAh cm–2for over 990 h. Besides, a laser-scribing designed flexible dual-plating-type microbattery based on a polyiodide ionic liquid cathode also exhibits stable cycling in both a single cell and 4 × 4 integrated cell, which can operate with the polarity-switching model with high stability.

Preeclampsia (PE) is a pregnancy complication characterized by placental dysfunction. However, the relationship between maternal blood markers and PE is unclear. It is helpful to improve the diagnosis and treatment of PE using new biomarkers related to PE in the blood. Three PE-related microarray datasets were obtained from the Gene Expression Synthesis database. The limma software package was used to identify differentially expressed genes (DEGs) between PE and control groups. Least absolute shrinkage and selection operator regression, support vector machine, random forest, and multivariate logistic regression analyses were used to determine key diagnostic biomarkers, which were verified using clinical samples. Subsequently, functional enrichment analysis was performed. In addition, the datasets were combined for immune cell infiltration analysis and to determine their relationships with core diagnostic biomarkers. The diagnostic performance of key genes was evaluated using the receiver operating characteristic (ROC) curve, C-index, and GiViTi calibration band. Genes with potential clinical applications were evaluated using decision curve analysis (DCA). Seventeen DEGs were identified, and 6 key genes (FN1, MYADM, CA6, PADI4, SLC4A10, and PPP4R1L) were obtained using 3 types of machine learning methods and logistic regression. High diagnostic performance was found for PE through evaluation of the ROC, C-index, GiViti calibration band, and DCA. The 2 types of immune cells (M0 macrophages and activated mast cells) were significantly different between patients with PE and controls. All of these genes except SLC4A10showed significant differences in expression levels between the 2 groups using quantitative reverse transcription-polymerase chain reaction. This model used 6 maternal blood markers to predict the occurrence of PE. The findings may stimulate ideas for the treatment and prevention of PE.

The electrochemical CO2reduction into formate acid over Pd-based catalysts under a wide potential window is a challenging task; CO poisoning commonly occurring on the vulnerable surface of Pd must be overcome. Herein, we designed a two-dimensional (2D) AuNP-in-PdNS electrocatalyst, in which the Au nanoparticles are intercalated in Pd nanosheets, for formate production under a wide potential window from −0.1 to −0.7 V versus a reversible hydrogen electrode. Based on the X-ray absorption spectra (XAS) characterizations, CO accumulation detection, and CO stripping voltammetry measurements, we observed that the intercalated Au nanoparticles could effectively avoid the CO formation and boost the formate production on the Pd nanosheet surface by regulating its electronic structure.

Electrochemical water splitting is a promising method for the renewable production of high-purity hydrogen via the hydrogen evolution reaction (HER). Ni−Fe layered double hydroxides (Ni−Fe LDHs) are highly efficient materials for mediating the oxygen evolution reaction (OER), a half-reaction for water splitting at the anode, but LDHs typically display poor HER performance. Here, we report the preparation of self-organized Ag@NiFe layered double hydroxide core-shell electrodes on Ni foam (Ag@NiFe/NF) prepared by galvanic etching for mediating both the HER and OER (bifunctional water-splitting electrocatalysis). This synthetic strategy allowed for the preparation of organized hierarchical architectures which displayed improved the electrochemical performance by tuning the electronic structure of the catalyst and increasing the surface area utilization. X-ray photoelectron spectroscopy (XPS) and theoretical calculations revealed that electron transfer from the Ni−Fe LDH to Ag influenced the adsorption of the reaction intermediates leading to enhanced catalytic activity. The Ag@NiFe/NF electrode displayed overpotentials as low as 180 and 80 mV for oxygen and hydrogen evolution, respectively, at a current density of 10 mA cm–2, and improvements in the specific activity by ∼5× and ∼1.5× for the oxygen and hydrogen evolution reaction, respectively, compared to benchmark NiFe hydroxide materials. Additionally, an integrated water-splitting electrolyzer electrode can be driven by an AA battery.

The electrochemical reduction of CO2is an effective approach to reduce and utilize CO2for carbon neutral under mild conditions, meanwhile, the development of efficient and stable catalysts with large area and low cost is more conducive to the industrialization of CO2electroreduction. The metal-oxide heterogeneous interface can promote the activation and conversion of CO2due to the synergy effect between the metal and the oxide. Therefore, Cu/In2O3electrodes are fabricated by magnetron sputtering in one step to achieve high selectivity of CO or CH3OH at different potentials. The highest Faradaic efficiency of CO is 78% at − 0.75 V, and unexpectedly, the Faradaic efficiency of CH3OH at − 0.55 V can reach 56%. The abundance of heterogeneous interfaces in Cu/In2O3provides more active sites, reduces the work function and shifts the d‐band center upward. The catalytic performance was improved by electron transfer promotion and enhanced CO adsorption. Such advantages are responsible for the unique catalytic properties of the metal-oxide electrodes and provide a novel insight to develop large area metal-oxide electrodes for CH3OH preparation.

Metallic 1T-phase MoS2is considered to be the ideal electrocatalyst to carry out hydrogen evolution reaction (HER) because of favorable conductivity and sufficient active site compared with 2H-phase MoS2. Nevertheless, 1T-phase MoS2is conventionally synthesized in a complicated process, with the production of an unstable product, which hinders their practical applications. Herein, we propose a facile approach through a carbon-doping-induced phase transition to obtain highly stable 1T–2H mixed MoS2nanosheets. The phase transition process is characterized by Raman and X-ray photoelectron spectroscopy, as well as high-resolution transmission electron microscopy images and delivers a high phase purity of ∼60% for 1T-MoS2. According to density functional theory simulations and experimental results, C-doped 1T–2H mixed MoS2has the advantages of abundant active sites, facilitated charge transfer rate, and high activity toward HER. The obtained C-doped MoS2exhibits a superb HER electrocatalytic performance, with a current density of 10 mA cm–2and the overpotential as low as 40 mV in 1 M KOH solution, and brilliant stability.

We designed dielectric gels, a new type of polymer-based dielectric material. By using solvents with high dielectric constants, the gels achieve a unique combination of ultra-high dielectric constant, low elastic modulus, and excellent transparency, which are extremely challenging or impossible to realize with traditional polymer dielectrics. The gels exhibit high stretchability (stretch of approximately 10) and low mechanical hysteresis. We demonstrated the use of the dielectric gels by fabricating a bioinspired tunable lens, the focal length of which can be adjusted by varying the applied voltage. We believe that the dielectric gels, as a new type of polymer dielectric, offer new opportunities for soft robotics, sensors, electronics, optics, and biomimetics. Stretchy and see-through substances known as dielectric gels may find application in soft robotics due to their capabilities of controllable movement. Insulating membranes can be stimulated to squeeze like a muscle by applying voltage pulses. Shujiang Ding from Xi’an Jiaotong University, China, and co-workers have developed a material that reduces the typically high voltages needed for movement by 50% compared with a commercial membrane. They used ultraviolet polymerization to lock liquid molecules with high charge-storing properties within a hydrocarbon chain network, producing super-insulating gels that can be extended up to 10 times their original size without damage. A bioinspired lens was fabricated by sandwiching a liquid between two gel membranes. Voltage-tunable pressure from the gels squeezed the lens and changed its focal length, similar to the changes seen in the human eye when focusing. Dielectric gels, a new type of polymer-based dielectric material have been designed. The gels achieve a unique combination of ultra-high dielectric constant, low elastic modulus, and excellent transparency, which are extremely challenging or impossible to realize by traditional polymer dielectrics. We have demonstrated the use of the dielectric gel by fabricating a bioinspired tunable lens, the focal length of which can be adjusted by varying the applied voltage. Dielectric gels offer new opportunities for soft robotics, sensors, electronics, optics, and biomimetics.

It still remains very challenging to design proper heterostructures to enhance the electrochemical performance of transition metal oxide-based anode materials for lithium-ion batteries. Here, we synthesized the NiCoO2nanosheets@SnO2layer heterostructure supported by amorphous carbon nanotubes (ACNTs) which is derived from polymeric nanotubes (PNTs) by a stepwise method. The inner SnO2layer not only provides a considerable capacity contribution but also produces the extra Li2O to promote the charge process of NiCoO2and thus results in a rising cycling performance. Combining with the contribution of ACNTs backbone and ultrathin NiCoO2nanosheets, the specific capacities of these one-dimensional nanostructures show an interesting gradually increasing trend even after 100 cycles at 400 mA g–1with a final result of 1166 mAh g–1. This approach can be an efficient general strategy for the preparation of mixed-metal-oxide one-dimensional nanostructures and this innovative design of hybrid electrode materials provides a promising approach for batteries with improved electrochemical performance.

The electrochemical reactions of O2, CO2 and their mixture in three structurally different ILs (i.e. 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf2]), 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ([BdMIM][NTf2]) and 1-butyl-1methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([BMPY][NTf2]) were thoroughly investigated by in-situ electrochemical quartz crystal microbalance (EQCM). Compared with single electrochemical method, the QCM integrated with electrochemical method was shown to be significantly more sensitive and powerful for characterization of the subtle differences (mass change or viscoselastic change) on IL/electrode interface. It is found that the CO2 reduction in ILs is irreversible and forms CO2*[?] adsorbate at electrode interface. With increasing concentrations of CO2, the reduction of oxygen is switched from a one electron process to overall two electron process, and forms adsorbed CO4*[?] intermediate species. Even though the mechanisms of electrochemical reaction between CO2 and electrochemical generated superoxide radical (O2*[?]) in three structurally different ILs are found to be similar, the simultaneously EQCM experimental results show that the different cation based ILs can modify the kinetics of the electrode reactions of O2 and CO2 due to a competition between the ILs cation and CO2 to react with O2*[?]. The reactivity of O2*[?] toward CO2 follows the order of the stability of the ILs cation under the O2*[?] attack, i.e. [BMPY][NTf2] > [BdMIM][NTf2] > [BMIM][NTf2].

Development of hydrogel-based flexible electronics with robust elasticity, low hysteresis, and excellent durability is still challenging. Herein, for the first time, B–N coordination was employed as the main driving force to promote gelation by free radical polymerization of acrylamide and 3-acrylamidophenylboronic acid. Owing to the outstanding stability of B–N coordination, the hydrogels could retain their initial stress (>95%) during 500 tension cycles (strain of 200%) with <10% hysteresis. Moreover, the addition of NaCl elevated the mechanical properties (break stress of 0.21 MPa and fracture strain of 1600%) and imparted high electrical conductivity (4.8 S/m) and superior gauge factor (10.2) to the hydrogels. The conductive hydrogels could accurately distinguish various deformations (2.5–200% tensile strain and 1–25 kPa compressive stress) and successively output reliable electrical signals with super durability (1000 tensile cycles with a strain of 100% and 1000 compressive cycles with a stress of 15 kPa). Combined with moderate tissue adhesiveness, the conductive hydrogels can monitor various human activities with constant outputs. This work offers a new solution to integrate high stretchability, robust elasticity, and low hysteresis into noncovalent cross-linked hydrogels, and may show vast potential in the development of flexible electronic devices.

Engineering heterojunction is an underlying strategy to develop remarkable electrocatalysts for carbon dioxide (CO2) reduction due to its ability to tune electronic properties by interfacial cooperation. Herein, we report a novel type of cube-like Zn2SnO4/SnO2heterostructure catalyst for CO2reduction through a simple co-precipitation process. The high-quality heterostructures with band alignment promote interfacial charge transfer from Zn2SnO4to SnO2, achieving the electronic modulation of Zn2SnO4/SnO2for reducing the kinetic barriers of CO2reduction. Density functional theory further reveals that Zn2SnO4/SnO2allows HCOO* intermediate favorably stabilizing on its surface through improved hydrogen coverage effect comparing to pure Zn2SnO4or SnO2. The hybrid catalyst presents satisfactory CO2reduction properties with a stable HCOOH selectivity of 77% during 24 h at −1.08 V vs. RHE. This study provides a new heterostructure modeling and general methodology for electronic modulation and electrocatalysts development for high-performance CO2reduction.

The electrochemical reactions of O2, CO2and their mixture in three structurally different ILs (i.e. 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf2]), 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ([BdMIM][NTf2]) and 1-butyl-1methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([BMPY][NTf2]) were thoroughly investigated by in-situ electrochemical quartz crystal microbalance (EQCM). Compared with single electrochemical method, the QCM integrated with electrochemical method was shown to be significantly more sensitive and powerful for characterization of the subtle differences (mass change or viscoselastic change) on IL/electrode interface. It is found that the CO2reduction in ILs is irreversible and forms CO2•−adsorbate at electrode interface. With increasing concentrations of CO2, the reduction of oxygen is switched from a one electron process to overall two electron process, and forms adsorbed CO4•−intermediate species. Even though the mechanisms of electrochemical reaction between CO2and electrochemical generated superoxide radical (O2•−) in three structurally different ILs are found to be similar, the simultaneously EQCM experimental results show that the different cation based ILs can modify the kinetics of the electrode reactions of O2and CO2due to a competition between the ILs cation and CO2to react with O2•−. The reactivity of O2•−toward CO2follows the order of the stability of the ILs cation under the O2•−attack, i.e. [BMPY][NTf2] > [BdMIM][NTf2] > [BMIM][NTf2].