Recent advances in fabrication and functions of neuromorphic system based on organic field effect transistor

The development of various artificial electronics and machines would explosively increase the amount of information and data,which need to be processed via in-situ remediation.Bioinspired synapse devices can store and process signals in a parallel way,thus improving fault tolerance and decreasing the power consumption of artificial systems.The organic field effect transistor(OFET)is a promising component for bioinspired neuromorphic systems because it is suitable for large-scale integrated circuits and flexible devices.In this review,the organic semiconductor materials,structures and fabrication,and different artificial sensory perception systems functions based on neuromorphic OFET devices are summarized.Subsequently,a summary and challenges of neuromorphic OFET devices are provided.This review presents a detailed introduction to the recent progress of neuromorphic OFET devices from semiconductor materials to perception systems,which would serve as a reference for the development of neuromorphic systems in future bioinspired electronics.

Enhanced selective hydrogenation of glycolaldehyde to ethylene glycol over Cu^(0)-Cu^(+)sites

Selective hydrogenation of hydroxyaldehydes to polyalcohols is challenging due to the competitive hydrogenation of C=O and CAO.This study develops heterogeneous Cu catalysts for the selective synthesis of ethylene glycol via batch liquid-phase hydrogenation of glycolaldehyde.SiO_(2)supported Cu,fabricated by ammonia evaporation,enables to catalyze the C=O bond hydrogenation with retaining the CAO bond intact,yielding higher selective hydrogenation activity with ethylene glycol selectivity up to 99.8%relative to MgO,Al_(2)O_(3),CeO_(2),and TiO_(2)supports and Cu/SiO_(2)synthesized by deposition–precipitation and impregnation.Characterizations confirm that highly efficient 20Cu/SiO_(2)-AE-623 K catalyst fabricated by ammonia evaporation is featured with larger Cu^(0)and Cu^(+)surface areas,of which the Cu^(+)species created from reducing copper phyllosilicate exhibit higher reactivity.A synergistic effect between Cu^(+)and Cu^(0)facilitates the selective adsorption/activation of glycolaldehyde on Cu^(+)sites and the dissociation of H_(2)on Cu^(0)sites,bringing a remarkable improvement in the selective hydrogenation performance.

Enhanced hydrodeoxygenation of lignin-derived anisole to arenes catalyzed by Mn-doped Cu/Al_(2)O_(3)

Lignin is a renewable carbon resource to produce arenes due to its abundant aromatic structures.For the liquid-phase hydrodeoxygenation(HDO)based on metallic catalysts,the preservation of aromatic rings in lignin or its derivatives remains a challenge.Herein,we synthesized Mndoped Cu/Al_(2)O_(3) catalysts from layered double hydroxides(LDHs)for liquid-phase HDO of lignin-derived anisole.Mn doping significantly enhanced the selective deoxygenation of anisole to arenes and inhibited the saturated hydrogenation on Cu/Al_(2)O_(3).With Mn doping increasing,the surface of Cu particles was modified with MnO_(x) along with enhanced generation of oxygen vacancies(Ov).The evolution of active sites structure led to a controllable adsorption geometry of anisole,which was beneficial for increasing arenes selectivity.As a result,the arenes selectivity obtained on 4Cu/8Mn4AlO_(x) was increased to be more than 6 folds of that value on 4Cu/4Al_(2)O_(3) over the synergistic sites between metal Cu and Ov generated on MnO_(x).

A comprehensive overview of the electrochemical mechanisms in emerging alkali metal-carbon dioxide batteries

Alkali metal-carbon dioxide(Li/Na/K-CO_(2))batteries are emerging electrochemical energy storage technologies in the context of the energy crisis and the urgent demand for carbon neutrality.Alkali metal-CO_(2) batteries offer a new strategy for CO_(2) fixation and utilization,and thus has been receiving considerable attention in recent years.Considerable progress has been achieved since alkali metal-CO_(2) batteries were invented,especially in terms of development of new electrode materials,and yet,research is lacking on the underlying mechanisms of the systems.This is the first typical review focusing on the electrochemical mechanisms of metal-CO_(2) batteries that summarizes the current understanding of and provides insights into the thermodynamic reaction pathways,the kinetic characteristics,and the crucial factors determining the reaction mechanisms in alkali metal-CO_(2) batteries.The review starts with the fundamental concepts of alkali metal-CO_(2) batteries,followed by a comprehensive discussion of the working mechanisms on cathodes and anodes.Moreover,the operation mechanisms of state-of-the-art electrolytes,including liquid and(quasi-)solid-state electrolytes,are also described.Finally,we identify the unsolved problems in current alkali metal-CO_(2) batteries and propose potential topics for future research.

Progress in Processes and Catalysts for Dehydrogenation of Cyclohexanol to Cyclohexanone

The dehydrogenation of cyclohexanol to cyclohexanone is a crucial industrial process in the production of caprolactam and adipic acid, both of which serve as important precursors in nylon textiles. This endothermic reaction is constrained by thermodynamic equilibrium and involves a complex reaction network, leading to a heightened focus on catalysts and process design. Copper-based catalysts have been extensively studied and exhibit exceptional low-temperature catalytic performance in cyclohexanol dehydrogenation, with some being commercially used in the industry. This paper specifically concentrates on research advancement concerning active species, reaction mechanisms, factors influencing product selectivity, and the deactivation behaviors of copper-based catalysts. Moreover, a brief introduction to the new processes that break thermodynamic equilibrium via reaction coupling and their corresponding catalysts is summarized here as well. These reviews may off er guidance and potential avenues for further investigations into catalysts and processes for cyclohexanol dehydrogenation.

Effect of solvents on the morphology and structure of barium titanate synthesized by a one-step hydrothermal method

Tetragonal barium titanate was synthesized from barium hydroxide octahydrate and titanium tetrachloride through a simple one-step hydrothermal method.The effect of different solvents on the crystal structure and morphology of barium titanate nanoparticles during the hy-drothermal process was investigated.Except for ethylene glycol/water solvent,impurity-free barium titanate was synthesized in pure water,methanol/water,ethanol/water,and isopropyl alcohol/water mixed solvents.Compared with other alcohols,ethanol promotes the formation of a tetragonal structure.In addition,characterization studies confirm that particles synthesized in methanol/water,ethanol/water,and isopropyl al-cohol/water mixed solvents are smaller in size than those synthesized in pure water.In the case of alcohol-containing solvents,the particle size decreases in the order of isopropanol,ethanol,and methanol.Among all the media used in this study,ethanol/water is considered the optimum reaction media for barium titanate with high tetragonality(defined as the ratio of two lattice parameters c and a,c/a=1.0088)and small aver-age particle size(82 nm),which indicates its great application potential in multilayer ceramic capacitors.

Thermal Shock-Activated Spontaneous Growing of Nanosheets for Overall Water Splitting

Nanomaterials based on nickel foam(NF) have been widely applied in energy conversion and storage field.Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable developments.Herein,we report a fast,simple,and low-cost synthesis method of nanomaterials based on NF by Joule-heating and water soaking treatment.Thin carbon-coated CoS on NF(NF-C/CoS) was synthesized by Joule-heating for a few seconds with rapid cooling.And then,NF-C/CoS/NiOOH with core-shell heterostructure was fabricated by soaking treatment of NF-C/CoS in water on which NiOOH nanosheets grew spontaneously.The formation mechanism is proposed that the coordination complex precursor converts into C/CoS on NF driven by Joule-heating,and the nickel on the surface of NF is activated to form metastable nickel simultaneously.The metastable nickel reacting with water leads to the formation of NiOOH,and the induction of CoS makes NiOOH grow continuously.This synthesis technology provides a new route to manufacture NF-based nanostructures,and the as-fabricated NF-C/CoS/NiOOH exhibits great potential as electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction.

Hollow structured Cu@ZrO_(2) derived from Zr-MOF for selective hydrogenation of CO_(2) to methanol

The development of a highly efficient catalyst for CO_(2) activation and selective conversion to methanol is critical to address the issues associated with the high thermal stability of CO_(2) and controllable synthesis of methanol.Cu-based catalysts have been widely studied because of the low cost and excellent performance in mild conditions.However,the improvement of catalytic activity and selectivity remains challenging.Herein,we prepared hollow Cu@ZrO_(2) catalysts through pyrolysis of Cu-loaded Zr-MOF for CO_(2) hydrogenation to methanol.Low-temperature pyrolysis generated highly dispersed Cu nanoparticles with balanced Cu^(0)/Cu^(+)sites,larger amounts of surface basic sites and abundant Cu-ZrO_(2) interface in the hollow structure,contributing to enhanced catalytic capacity for adsorption/activation of CO_(2) and selective hydrogenation to methanol.In situ Fourier Transform Infrared Spectroscopy revealed the methanol formation followed the formate-intermediated pathway.This work would provide a guideline for the design of high-performance catalysts and the understanding of the mechanism and active sites for CO_(2) hydrogenation to methanol.

Aqueous Two-Phase Interfacial Assembly of COF Membranes for Water Desalination

Aqueous two-phase system features with ultralow interfacial tension and thick interfacial region,affording unique confined space for membrane assembly.Here,for the first time,an aqueous two-phase interfacial assembly method is proposed to fabricate covalent organic framework(COF)membranes.The aqueous solution containing polyethylene glycol and dextran undergoes segregated phase separation into two water-rich phases.By respectively distributing aldehyde and amine monomers into two aqueous phases,a series of COF membranes are fabricated at water-water interface.The resultant membranes exhibit high NaCl rejection of 93.0-93.6% and water permeance reaching 1.7-3.7 L m^(−2) h^(−1) bar^(−1),superior to most water desalination membranes.Interestingly,the interfacial tension is found to have pronounced effect on membrane structures.The appropriate interfacial tension range(0.1-1.0 mN m^(−1))leads to the tight and intact COF membranes.Furthermore,the method is extended to the fabrication of other COF and metal-organic polymer membranes.This work is the first exploitation of fabricating membranes in all-aqueous system,confering a green and generic method for advanced membrane manufacturing.

Highly dispersed nickel boosts catalysis by Cu/SiO_(2) in the hydrogenation of CO_(2)-derived ethylene carbonate to methanol and ethylene glycol

The efficient hydrogenation of CO_(2)-derived ethylene carbonate(EC)to yield methanol(MeOH)and ethylene glycol(EG)is a key process for indirect conversion of CO_(2)to MeOH.However,a high H_(2)/EC molar ratio during the hydrogenation process(usually as 180-300)is generally required to achieve good catalytic performance,resulting in high cost and energy consumption for H_(2)circulation in the promising industrial application.Here,we prepared a series of Ni-modified Cu/SiO_(2)catalysts and explored the effects of synthesis methods and Ni contents on catalytic performance under different H_(2)/EC molar ratios.The Cu/SiO_(2)catalyst with 0.2%(mass)Ni loading prepared by co-ammonia evaporation method exhibited above 99%conversion of EC,91%and 98%selectivity to MeOH and EG respectively at H_(2)/EC ratio of 60.And no significant deactivation was observed within 140 h at a lower H_(2)/EC of 40.It is demonstrated that a few of Ni addition could not only promote Cu dispersion and increase surface Cu^(+) species due to the strong interaction between Cu and Ni species,but also form uniformly-dispersed CuNi alloy species and thus enhance the adsorption and dissociation of H_(2).But the excess Ni species would aggregate and segregate to cover partial surface of Cu nanoparticles,leading to a significantly drop of catalytic performance in EC hydrogenation.These insights may provide guidance for further design of catalysts for the ester hydrogenation reactions.

Enhanced chemical trapping and catalytic conversion of polysulfides by diatomite/MXene hybrid interlayer for stable Li-S batteries

Lithium-Sulfur (Li-S) batteries with high theoretical energy density are promising energy storage systems in the next decades, while the lithium polysulfides (LiPSs) shuttling caused by the sluggish sulfur redox reaction severely lowers the practical performance. The use of interlayer between the cathode and separator has been widely investigated to physically or chemically block the LiPSs, while the introduction of catalytic materials is a more effective strategy to accelerate the conversion of LiPSs. MXene with rich surface chemistry has shown its potential for facilitating the catalytic conversion, however, the aggregation of MXene sheets usually leads to the loss of the catalytic active sites. Herein, we report a diatomite/MXene (DE/MX) hybrid material as the bifunctional interlayer for improving the adsorption/conversion of LiPSs in Li-S batteries. The diatomite with porous structure and rich silica-hydroxyl functional groups could trap LiPSs effectively, while prevent the aggregation of MXene. The DE/MX based interlayer showed bifunctions of enhancing the chemical adsorption and promoting the conversion of LiPSs. The Li-S batteries with the DE/MX interlayer delivered an improved cycling stability with a low capacity decay of 0.059% per cycle over 1000 cycles at 1.0 C. Moreover, stable 200 cycles can be realized with a high sulfur loading electrode up to 6.0 mg cm^(−2). This work provides an effective strategy to construct bifunctional interlayers for hindering the shuttling of LiPSs and boosting the practical application of Li-S batteries.

Rational Manipulation of Intermediates on Copper for CO_(2)Electroreduction Toward Multicarbon Products

Excess greenhouse gas emissions,primarily carbon dioxide(CO_(2)),have caused major environmental concerns worldwide.The electroreduction of CO_(2)into valuable chemicals using renewable energy is an ecofriendly approach to achieve carbon neutrality.In this regard,copper(Cu)has attracted considerable attention as the only known metallic catalyst available for converting CO_(2)to high-value multicarbon(C_(2+))products.The production of C_(2+)involves complicated C-C coupling steps and thus imposes high demands on intermediate regulation.In this review,we discuss multiple strategies for modulating intermediates to facilitate C_(2+)formation on Cu-based catalysts.Furthermore,several sophisticated in situ characterization techniques are outlined for elucidating the mechanism of C-C coupling.Lastly,the challenges and future directions of CO_(2)electroreduction to C_(2+)are envisioned.

Recent Developments of Antimony-Based Anodes for Sodiumand Potassium-Ion Batteries

The development of sodium-ion(SIBs)and potassium-ion batteries(PIBs)has increased rapidly because of the abundant resources and cost-effectiveness of Na and K.Antimony(Sb)plays an important role in SIBs and PIBs because of its high theoretical capacity,proper working voltage,and low cost.However,Sb-based anodes have the drawbacks of large volume changes and weak charge transfer during the charge and discharge processes,thus leading to poor cycling and rapid capacity decay.To address such drawbacks,many strategies and a variety of Sb-based materials have been developed in recent years.This review systematically introduces the recent research progress of a variety of Sb-based anodes for SIBs and PIBs from the perspective of composition selection,preparation technologies,structural characteristics,and energy storage behaviors.Moreover,corresponding examples are presented to illustrate the advantages or disadvantages of these anodes.Finally,we summarize the challenges of the development of Sb-based materials for Na/K-ion batteries and propose potential research directions for their further development.

Pt-modulated Cu/SiO_(2) catalysts for efficient hydrogenation of CO_(2)-derived ethylene carbonate to methanol and ethylene glycol

Copper-based catalysts were widely used in the heterogeneous selective hydrogenation of ethylene carbonate(EC),a key step in the indirect conversion of CO_(2) to methanol.However,a high H_(2)/EC molar ratio in feed is required to achieve favorable activity and the methanol selectivity still needs to be improved.Herein,we fabricated a series of Pt-modulated Cu/SiO_(2) catalysts and investigated their catalytic performance for hydrogenation of EC in a fixed bed reactor.By modulating the Pt amount,the optimal 0.2Pt-Cu/SiO_(2) catalyst exhibited the highest catalytic performance with99%EC conversion,over 98%selectivity to ethylene glycol and 95.8%selectivity to methanol at the H_(2)/EC ratio as low as 60 in feed.In addition,0.2Pt-Cu/SiO_(2) catalyst showed excellent stability for 150 h on stream over different H_(2)/EC ratios of 180-40.It is demonstrated a proper amount of Pt could significantly lower the H_(2)/EC molar ratio,promote the reducibility and dispersion of copper,and also enhance surface density of Cu+species.This could be due to the strong interaction of Cu and Pt induced by formation of alloyed Pt single atoms on the Cu lattice.Meanwhile,a relatively higher amount of Pt would deteriorate the catalytic activity,which could be due to the surface coverage and aggregation of active species.These findings may enlighten some fundamental insights for further design of Cu-based catalysts for the hydrogenation of carbon–oxygen bonds.

Understanding the effects of electrode meso-macropore structure and solvent polarity on electric double layer capacitors based on a continuum model

The structures of electrode meso-macropore and the solvent polarity are the crucial factors dominating the performance of the electric double layer capacitors(EDLCs),but their impacts are usually tangled and difficult to decouple and quantitate.Here the effects of electrode meso-macropore structure and solvent polarity on the specific capacitance of an EDLC are quantitatively investigated using a steady-state continuum model.The simulation results indicate the specific capacitances are significantly affected by the meso-macropore surface structure.The specific capacitances significantly decrease for both convex surface structures but obviously increase for both concave surface structures,with the increase of curvature radius from 1 to 20 nm.As for solvents,the polar solvent with high saturated dielectric permittivity improves the capacitance performance.Moreover,the electrode meso-macropore structure is of more concern compared with solvent polarity when aiming at enhancing the specific capacitance.These results provide fundamentals for the rational design of porous electrodes and polar electrolytes for EDLCs.

Regulation of Oxygen Activity by Lattice Confinement over Ni_(x)Mg_(1-x)O Catalysts for Renewable Hydrogen Production

The chemical looping steam reforming(CLSR)of bioethanol is an energy-efficient and carbon-neutral approach of hydrogen production.This paper describes the use of a Ni_(x)Mg_(1-x)O solid solution as the oxy-gen carrier(OC)in the CLSR of bioethanol.Due to the regulation effect of Mg^(2+)in Ni_(x)Mg_(1-x)O,a three-stage reaction mechanism of the CLSR process is proposed.The surface oxygen of Ni_(x)Mg_(1-x)O initially causes complete oxidation of the ethanol.Subsequently,H_(2)O and bulk oxygen confined by Mg^(2+)react with etha-nol to form CH_(3)COO^(*)followed by H_(2) over partially reduced Ni_(x)Mg_(1-x)O.Once the bulk oxygen is con-sumed,the ethanol steam reforming process is promoted by the metallic nickel in the stage Ⅲ.As a result,Ni_(0.4)Mg_(0.6)O exhibits a high H_(2) selectivity(4.72 mol H_(2) per mole ethanol)with a low steam-to-carbon molar ratio of 1,and remains stable over 30 CLSR cycles.The design of this solid-solution OC pro-vides a versatile strategy for manipulating the chemical looping process.

Confining Li_(2)O_(2) in tortuous pores of mesoporous cathodes to facilitate low charge overpotentials for Li-O_(2) batteries

Achieving low charge overpotentials represents one of the most critical challenges for pursuing highperformance lithium-oxygen(Li-O_(2))batteries.Herein,we propose a strategy to realize low charge overpotentials by confining the growth of lithium peroxide(Li_(2)O_(2))inside mesoporous channels of cathodes(CMK-8).The CMK-8 cathode with tortuous pore structures can extend the diffusion distance of lithium superoxide(LiO_(2))in the mesoporous channels,facilitating the further reduction of LiO_(2) to lithium peroxide(Li_(2)O_(2))inside the pores and preventing them to be diffused out of the pores.Therefore,Li_(2)O_(2) is trapped in the mesoporous channels of CMK-8 cathodes,ensuring a good Li_(2)O_(2)/CMK-8 contact interface.The CMK-8 electrode exhibits a low charge overpotential of 0.43 V and a good cycle life for 72 cycles with a fixed capacity of 500 m Ah g^(-1) at 0.1 A g^(-1).This study proposes a strategy to achieve a low charge overpotential by confining Li_(2)O_(2) growth in the mesoporous channels of cathodes.

How the surface Cu layer affected the activity of Ni foil for alkaline hydrogen evolution

Synthesizing bimetallic nanomaterials,with noble metals as the surface layers and inert metals as the substrates,has been proven to be an effective way to reduce the use of noble metals with maintained catalytic activity.However,an atomic diffusion from the inert substrate to the surface during the long-term operation has been reported to significantly decrease the activity.In this work,a series of catalysis-inert Cu-coated Ni foil were fabricated through electrodeposition and their activities for alkaline hydrogen evolution were investigated.Notably,the Ni/Cu-60 sample showed a similar catalytic property with pure Ni foil and only a slight decrease in HER activity was observed.The X-ray photoelectron spectroscopy(XPS)results indicated a decreased electron concentration of Cu in Ni/Cu-60,and theoretical calculations further demonstrated the electron transfer between the Ni substrate and Cu layer.Our results reveal that a specific composition or structure of an inert metal layer might not significantly decrease the electrocatalytic activity of active metals.Moreover,there are more possibilities for the rational design of metal-based catalysts for electrocatalysis.

Design and modification of metal sulfide-based catalysts for lithiumsulfur batteries

Metal sulfide(MS)have good conductivity,strong adsorption ability,and excellent catalytic activity for the conversion of sulfur species,and thus,show great promise as the catalysts in LieS batteries.However,the relationship between their properties and electrochemical performance is still unclear.Thus,further in-depth discussions are required to improve their design in Li-S batteries.This review systematically summarizes the basic structural and electrochemical properties of MSs and highlights the advantages that guarantee them as high-performance catalysts in Li-S batteries.Then,various modification strategies for MSs to enhance the catalytic activity,efficiency,and stability are also reviewed.At last,future opportunities for MS catalysts in Li-S batteries are proposed.

Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first cycle.In this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing agent.We show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the performance.We obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg doping.By the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).