Aqueous Zn-ion batteries(AZIBs)have been regarded as promising alternatives to Li-ion batteries due to their advantages,such as low cost,high safety,and environmental friendliness.However,AZIBs face significant challe...Aqueous Zn-ion batteries(AZIBs)have been regarded as promising alternatives to Li-ion batteries due to their advantages,such as low cost,high safety,and environmental friendliness.However,AZIBs face significant challenges in limited stability and lifetime owing to zinc dendrite growth and serious side reactions caused by water molecules in the aqueous electrolyte during cycling.To address these issues,a new eutectic electrolyte based on Zn(ClO_(4))_(2)·6H_(2)O-N-methylacetamide(ZN)is proposed in this work.Compared with aqueous electrolyte,the ZN eutectic electrolyte containing organic N-methylacetamide could regulate the solvated structure of Zn^(2+),effectively suppressing zinc dendrite growth and side reactions.As a result,the Zn//NH4 V4 O10 full cell with the eutectic ZN-1-3 electrolyte demonstrates significantly enhanced cycling stability after 1000 cycles at 1 A g^(-1).Therefore,this study not only presents a new eutectic electrolyte for zinc-ion batteries but also provides a deep understanding of the influence of Zn^(2+)solvation structure on the cycle stability,contributing to the exploration of novel electrolytes for high-performance AZIBs.展开更多
This article investigated the factors and mechanisms that affected the workability and mechanical properties of cement paste incorporating nano-TiO_(2).The findings indicated that,for nano-TiO_(2)aqueous solution conc...This article investigated the factors and mechanisms that affected the workability and mechanical properties of cement paste incorporating nano-TiO_(2).The findings indicated that,for nano-TiO_(2)aqueous solution concentrations of 3%,6%,9%,and 12%,the optimal dispersion effect was achieved with an ultrasonic dispersion time of 20 minutes.Specifically,at a 6%nano-TiO_(2)content,both the workability and mechanical performance of the cement paste were enhanced.Furthermore,while nano-TiO_(2)did not alter the types of hydration products present in the cement paste,it did increase the amount of C-S-H gels.This enhancement was attributed to a higher number of nucleation sites for hydration products,which promoted hydration and reduced the porosity of the cement paste.展开更多
Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced eff...Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced effect on both the particle size and the extent of agglomeration.With the increase in methanol content,the particle size and agglomeration of CuF_(2) decreased first and then increased.When the volume ratio of methanol to deionized water was 1:1,the CuF_(2) particles exhibited the smallest size and the lowest degree of agglomeration.CuF_(2) synthesized with 50%methanol exhibited superior electrochemical performances with a voltage plateau above 3 V and a 1st discharge capacity of 525.8 mAh·g^(-1) at 0.01 C due to the synergistic influence of the particle size and dispersion.The analysis results using electrochemical impedance spectroscopy(EIS)and constant current intermittent titration technique(GITT)affirmed the addition of methanol was beneficial for promoting Li+diffusion and accelerating electrochemical reaction kinetics of CuF_(2).展开更多
The electrochemical performance of layered O3-type NaCrO_(2)cathode material is significantly affected by the side reactions between NaCrO_(2)and electrolyte during sodium storage.A uniform Cr_(2)O_(3)coating layer wa...The electrochemical performance of layered O3-type NaCrO_(2)cathode material is significantly affected by the side reactions between NaCrO_(2)and electrolyte during sodium storage.A uniform Cr_(2)O_(3)coating layer was in situ constructed on the surface of NaCrO_(2)by controlling the excess ratio of sodium source.The structure,morphology,valence and electrochemical performance of the Cr_(2)O_(3)-coated NaCrO_(2)were characterized.The results indicate that the Cr_(2)O_(3)coating layer does not alter the crystal structure and morphology of NaCrO_(2),but effectively suppresses the side reactions between NaCrO_(2)and electrolyte,and improves the surface/interfacial stability of NaCrO_(2)material.The Cr_(2)O_(3)-coated NaCrO_(2)exhibits improved electrochemical performance with a capacity retention of 66.4%after 500 cycles at 10C.展开更多
Coating techniques are efficient routes to modify surface property of composite membranes for enhanced membrane separations.However,it remains challenge to deposit continuous inorganic layers on hollow fiber substrate...Coating techniques are efficient routes to modify surface property of composite membranes for enhanced membrane separations.However,it remains challenge to deposit continuous inorganic layers on hollow fiber substrates.This study combines surface segregation with physical vapor deposition(PVD)to construct intensified TiO_(2)layers on polyether sulfone(PES)hollow fiber substrates.During membrane fabrication,polyethylene-polypropylene glycol(F127)is used as surface segregation agent in casting solution,which enables PES hollow fibers with abundant hydroxy groups,thus improving the compatibility between PES and vaporized TiO_(2).The obtained PES/F127@TiO_(2)membranes exhibit tight TiO_(2)layers with tunable thickness,high mechanical strength,narrowed pore size and enhanced hydrophilicity.Moreover,the optimized PES/F127@TiO_(2)membranes show competitive antifouling performances in water treatment,with a water permeability up to 97 L·m^(-2)·h^(-1)·bar^(-1)and bovine serum albumin(BSA)rejection of~99%.This work is expected to provide a material design idea to deposit functional layers on polymers for fortified performances.展开更多
This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated thro...This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated through an innovative strategy involving Sn electrodeposition,oxidation,and MnO_(2)-layer preparation.The structure of the anode was characterized,and the oxygen evolution performance was evaluated in a H_(2)SO_(4) solution.The results show that compared with the Ti/SnO_(2)/MnO_(2) anode prepared by the conventional brushing-annealing process,the Ti/SnO_(x)/MnO_(2) anode fabricated through the innovative procedure exhibits a lower oxygen evolution potential and a nearly 40%longer accelerated lifespan.The superior oxygen evolution performance of the Ti/SnO_(x)/MnO_(2) anode is attributed to the distinctive SnO_(x) intermediate layer fabricated through Sn electrodeposition followed by oxidation,which indicates the great potential of the anode as a dimensionally stable anode for metal electrowinning and hydrogen production by electrolysis,etc.展开更多
Mg_(3)Bi_(2)-based flms are promising near-room-temperature thermoelectric materials for the development of fexible thermoelectric devices.However,the high hole concentration caused by the abundance of intrinsic Mg va...Mg_(3)Bi_(2)-based flms are promising near-room-temperature thermoelectric materials for the development of fexible thermoelectric devices.However,the high hole concentration caused by the abundance of intrinsic Mg vacancies easily leads to deterioration of electrical properties,especially for p-type Mg_(3)Bi_(2) flm.And the optimization of thermal conductivity of the Mg_(3)Bi_(2)-based flms is barely investigated.In this work,we demonstrate the improved thermoelectric performances of p-type Mg_(3)Bi_(2) through Ag doping by magnetron sputtering.This doping successfully reduces the hole concentration and broadens the band gap of Mg_(3)Bi_(2),thus resulting in a peak power factor of 442μW m−1 K−2 at 525 K.At the same time,Ag doping-induced fuctuations in mass and microscopic strain efectively enhanced the phonon scattering to reduce the lattice thermal conductivity.Consequently,a maximum thermoelectric fgure of merit of 0.22 is achieved at 525 K.Its near-roomtemperature thermoelectric performances demonstrate superior performance compared to many Mg_(3)Bi_(2)-based flms.To further evaluate its potential for thermoelectric power generation,we fabricated a thermoelectric device using Ag-doped Mg_(3)Bi_(2) flms,which achieved a power density of 864μW cm⁻2 at 35 K temperature diference.This study presents an efective strategy for the advancement of Mg_(3)Bi_(2)-based flms for application in micro-thermoelectric devices.展开更多
Neuromorphic devices have shown great potential in simulating the function of biological neurons due to their efficient parallel information processing and low energy consumption.MXene-Ti_(3)C_(2)T_(x),an emerging two...Neuromorphic devices have shown great potential in simulating the function of biological neurons due to their efficient parallel information processing and low energy consumption.MXene-Ti_(3)C_(2)T_(x),an emerging twodimensional material,stands out as an ideal candidate for fabricating neuromorphic devices.Its exceptional electrical performance and robust mechanical properties make it an ideal choice for this purpose.This review aims to uncover the advantages and properties of MXene-Ti_(3)C_(2)T_(x)in neuromorphic devices and to promote its further development.Firstly,we categorize several core physical mechanisms present in MXene-Ti_(3)C_(2)T_(x)neuromorphic devices and summarize in detail the reasons for their formation.Then,this work systematically summarizes and classifies advanced techniques for the three main optimization pathways of MXene-Ti_(3)C_(2)T_(x),such as doping engineering,interface engineering,and structural engineering.Significantly,this work highlights innovative applications of MXene-Ti_(3)C_(2)T_(x)neuromorphic devices in cutting-edge computing paradigms,particularly near-sensor computing and in-sensor computing.Finally,this review carefully compiles a table that integrates almost all research results involving MXene-Ti_(3)C_(2)T_(x)neuromorphic devices and discusses the challenges,development prospects,and feasibility of MXene-Ti_(3)C_(2)T_(x)-based neuromorphic devices in practical applications,aiming to lay a solid theoretical foundation and provide technical support for further exploration and application of MXene-Ti_(3)C_(2)T_(x)in the field of neuromorphic devices.展开更多
In this work,the TiO_(2)/Sb_(2)S_(3) nanorod arrays(NRAs)were synthesized through a two-stage hydrothermal route for photoelectrochemical(PEC)water splitting.The effect of annealing treatment in Ar ambience on the PEC...In this work,the TiO_(2)/Sb_(2)S_(3) nanorod arrays(NRAs)were synthesized through a two-stage hydrothermal route for photoelectrochemical(PEC)water splitting.The effect of annealing treatment in Ar ambience on the PEC activity of TiO_(2)/Sb_(2)S_(3) composite sample was investigated by electrochemical impedance analysis,including Nyquist and Mott-Schottky(M-S)plots.It was demonstrated that vacuum annealing could crystallize Sb_(2)S_(3) component and change its color from red to black,leading to an increment of photocurrent density from 1.9 A/m^(2) to 4.25 A/m^(2) at 0 V versus saturated calomel electrode(VSCE).The enhanced PEC performance was mainly attributed to the improved visible light absorption.Moreover,annealing treatment facilitated retarding the electron-hole recombination occurred at the solid/liquid interfaces.Our work might provide a novel strategy for enhancing the PEC performance of a semiconductor electrode.展开更多
To explore the effect of sulfur vacancies in transition metal sulfide on the electrochemical properties of anode materials,the graphene oxide(GO)and CoNi2S4 were used as the raw materials to synthesize the rGO_(10)−Co...To explore the effect of sulfur vacancies in transition metal sulfide on the electrochemical properties of anode materials,the graphene oxide(GO)and CoNi2S4 were used as the raw materials to synthesize the rGO_(10)−CoNi_(2)S_(4−x)composite electrode materials by the solvothermal method.The obtained rGO_(10)−CoNi_(2)S_(4−x)electrode materials with sulfur vacancies consist of nanoflakes and nanorods.The galvanostatic charge−discharge test of the rGO_(10)−CoNi_(2)S_(4−x)electrode materials shows a great specific capacitance of 3050.1 F/g at a current density of 1 A/g.Moreover,the electrode materials still remain rate capability retention of 86.1%when the current density increases from 1 to at 10 A/g.The rGO_(10)−CoNi_(2)S_(4−x)composite containing sulfur vacancies has higher specific capacitance and better rate capability in comparison to the pristine rGO−CoNi2S4 without containing sulfur defects.The optimized rGO_(10)−CoNi_(2)S_(4−x)composite electrode materials with sulfur vacancies exhibit outstanding cycle stability and rate performance.展开更多
To evaluate the effects of solar greenhouse with different structure and CO2 enrichment on illumination and temperature performance of greenhouse and cucumber growth and development in the central region of Inner Mong...To evaluate the effects of solar greenhouse with different structure and CO2 enrichment on illumination and temperature performance of greenhouse and cucumber growth and development in the central region of Inner Mongolia, the research used traditional solar greenhouse （A） and blanket-inside solar greenhouse（B）, and set 4 treatments： AE （traditional solar greenhouse A with CO2 enrichment）, AN （traditional solar greenhouse A without CO2 enrichment）, BE （blanket-inside solar greenhouse B with CO2 enrichment） and BN （blanket-inside solar greenhouse B without CO2 enrichment）, to explore the influence of cucumber growth, photosynthetic property, quality and yield in different structure solar greenhouses with CO2 enrichment. The results showed that the illumination and temperature in blanket-inside solar greenhouse was superior to traditional solar greenhouse, and the average light intensity in blanket-inside solar greenhouse increased by 21.05%, compared with traditional solar greenhouse. Under the condition of same greenhouse structure, stem height ,average stem diameter, contents of soluble sugar, vitamin C, net photosynthetic rate and yield showed any significant difference between the treatments with CO2 enrichment or not. Under the condition of same CO2 concentration, BE cucumber average stem height, average stem diameter, contents of soluble sugar, net photosynthetic rate and yield in BE was higher than which in AE. Therefore, the optimization in structure of blanket-inside solar greenhouse remarkably improved illumination and temperature property, combining with CO2 enrichment as application technology, there was crucial significance to promote the greenhouse performance and improve the efficiency of greenhouse vegetable production.展开更多
Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction.Herein,a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis metho...Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction.Herein,a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis method.The as-prepared samples had a large specific surface area(up to 2512 m^(2)/g),a moderate-high N content(up to 4.82 at.%),and high population(55%)of ultra-micropores(<0.7 nm).Regulating the N content and ultra-microporosity led to efficient CO_(2)adsorption and separation.At ambient pressure,the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO_(2)uptake of 4.25 mmol/g at 25℃ and 6.57 mmol/g at 0℃.These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis,primarily due to the existence of ultra-micropores.The sample exhibited excellent CO_(2)/N_(2)selectivity at 25℃ owing to the abundant basic pyridinic and pyrrolic N species;and showed superior CO_(2)adsorption-desorption cycling performance,which was maintained at 97% after 10 cycles at 25℃.Moreover,petroleum coke-based microporous carbon,with a considerably high specific surface area and hierarchical pore structure,exhibited excellent electrochemical performance over the N-doped sample,maintaining a favorable specific capacitance of 233.25F/g at 0.5 A/g in 6 mol/L KOH aqueous electrolyte.This study provides insight into the influence of N-doping on the porous properties of petroleum coke-based carbon.Furthermore,the as-prepared carbons were found to be promising adsorbents for CO_(2)adsorption,CO_(2)/N_(2)separation and electrochemical application.展开更多
To meet the demand for high-performance LiCoO_(2) batteries,it is necessary to overcome challenges such as interface degradation and rapid capacity degradation caused by changes in bulk structure,especially under deep...To meet the demand for high-performance LiCoO_(2) batteries,it is necessary to overcome challenges such as interface degradation and rapid capacity degradation caused by changes in bulk structure,especially under deep delithiation and high temperature conditions.The ion conductive coating layer of Li_(3)PO_(4) has been directly modified on the surface of LiCoO_(2) particles using magnetron sputtering method,significantly improving the lithium storage performance of LiCoO_(2)@Li_(3)PO_(4) composites.Compared to pure LiCoO_(2),the modified LiCoO_(2) sample exhibits obviously better cycle life and high-temperature performance.Especially,under the conditions of 2 and 1 C,the LiCoO_(2)@Li_(3)PO_(4) electrode delivers excellent cycling performance at high voltage of 4.5 V,with capacity retention rates of 89.7%and 75.7%at room temperature and high temperature of 45℃,being far greater than those of 12.3%and 29.1%for bare LiCoO_(2) electrodes.It is discovered that the Li_(3)PO_(4) coating layer not only effectively enhances interface compatibility and suppresses the irreversible phase transition of LiCoO_(2),but also further improves the Li^(+)transport kinetics and significantly reduces battery polarization,ultimately enabling the modified LiCoO_(2) electrode to exhibit excellent lithium storage performance and thermal safety characteristics under high voltage conditions.Thus,such effective modified strategy can undoubtedly provide an important academic inspiration for LiCoO_(2) implication.展开更多
CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state d...CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.展开更多
Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability ...Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in practice.In this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above challenges.Co doping can effectively widen layer spacing and reduce Li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side reactions.Therefore,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) coating.Its capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.展开更多
The demand for sustainable and stretchable thin-film printed batteries for bioelectronics,wearables,and e-textiles is rapidly increasing.Recently,we developed a fully 3D-printed soft-matter thin-film Ga-Ag_(2)O batter...The demand for sustainable and stretchable thin-film printed batteries for bioelectronics,wearables,and e-textiles is rapidly increasing.Recently,we developed a fully 3D-printed soft-matter thin-film Ga-Ag_(2)O battery with 3R characteristics:resilient to mechanical strain,repairable after damage,and recyclable.This battery achieved a record-breaking areal capacity of 26.37 mAh cm-2,increasing to 30.32 mAh cm^(-2) after 10 cycles under 100%strain.This performance stems from the synergistic effects of gallium’s liquid metal properties and the styrene-isoprene-styrene polymer in the anode.Gallium’s high specific capacity(1153.2 mAh g^(-1)),deformability,and self-healing abilities,supported by its supercooled liquid phase,significantly enhance the battery’s resilience and efficiency.However,the cathode’s lower theoretical capacity,due to Ag_(2)O(231.31 mAh g^(-1)),remains a limitation.Traditional Ag_(2)O-carbon black-styrene-isoprene-styrene cathodes experience rapid capacity decay as only the surface area of the active materials interacts with the electrolyte.To overcome this,we designed a carbon-filled Ag_(2)O foam electrode using a sacrificial sugar template,increasing the effective surface area.This optimization enhanced ion-exchange efficiency,specific capacity,and cyclability,achieving a specific capacity of 221.16 mAh g^(-1).Consequently,the Ga-Ag_(2)O stretchable battery attained a record areal capacity of 40.91 mAh cm^(-2)—double that of nonfoam electrodes—and exhibited fivefold improved charge-discharge cycles.Using ultrastretchable Ag-EGaIn-styrene-isoprene-styrene and carbon black-styrene-isoprene-styrene current collectors,the battery’s specific capacity increased by 33%under 50%strain.Integrated into a soft-matter smart wristband for temperature monitoring,the battery demonstrated its promise for wearable electronics.展开更多
Achieving broadband solar thermal absorption via dilute nanofluids is still a daunting challenge since the absorption peaks of common metal particles are usually located in the visible part of the radiation spectrum.T...Achieving broadband solar thermal absorption via dilute nanofluids is still a daunting challenge since the absorption peaks of common metal particles are usually located in the visible part of the radiation spectrum.This paper aims to present the results of experimental investigations on the thermal performance of heat pipe-type evacuated solar collectors.The experimented system consists of 15 tubes,providing the hot nanofluid to 100-L storage in a closed flow loop.The solar collector with a gross area of 2.1 m^(2)is part of the solar hot water test system located in Baghdad-Iraq.Al2O3 nanofluid at 0.5%volume concentration in water as working fluid was used in three flow rates of 3.3,6.6,and 10 L/min over two months,March and April.The experimental results indicated that maximum solar irradiation was 1070 and 1270 W/m^(2)in March and April,respectively.The maximum daily average of rate heat gain 11,270 and 12,040 W was recorded in March and April,respectively.In terms of the best operational flow rate,the system performs better at 3.3 L/min nanofluid flow rate.For the considered study period,the average monthly maximum energy efficiencies of the solar collector in March and April were 86%and 80%,respectively.展开更多
Tin sulfide(SnS_(2))anodes have garnered significant attention within emerging energy storage technologies.However,the application of SnS_(2)is curtailed due to its inherent limitations,including poor cyclic stability...Tin sulfide(SnS_(2))anodes have garnered significant attention within emerging energy storage technologies.However,the application of SnS_(2)is curtailed due to its inherent limitations,including poor cyclic stability and inevitable volumetric expansion upon cycling.This study reports the successful fabrication of an innovative SnS_(2)-based composite,featuring an eggshell-like structured nitrogen-doped carbon coating,referred to as SnS_(2)@NxC.This novel architecture,wherein SnS_(2)acts as the core encapsulated by a nitrogen-doped carbon shell,characterized by a void space between the shell and core,is crucial in mitigating volumetric expansion.This configuration contributes to maintaining the structural integrity of the composite materials,even under the stresses of continuous cycling.Nitrogen within the carbon matrix enhances conductivity and promotes the formation of a more robust and stable solid electrolyte interphase(SEI)layer.Experimental investigations have substantiated the electrochemical superiority of the SnS_(2)@NxC electrode,demonstrating a specific capacity of 701.8 mA·h·g^(-1)after 1000 cycles at 0.5 A·g^(-1)and maintaining a capacity of 597.2mA·h·g^(-1)after 400 cycles at a heightened current density of 2 A·g^(-1).These findings underscore the exceptional cyclic performance and durability of the SnS_(2)@NxC electrode.展开更多
The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)conta...The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)contamination on the gas diffusion layer(GDL)and PEMFC performance,systematically analyzing the physicochemical property changes and their correlation with electrochemical performance.The results indicate that after post-treatment,the GDL surface exhibited exposed carbon fibers,cracks,and large pores in the microporous layer(MPL),with a noticeable detachment of PTFE.There was a marked reduction in C and F element signals,an increase in O element signals,deposition of Cr_(2)(SO_(4))_(3),formation of C=O and C=C bonds,appearance of Cr_(2)(SO_(4))_(3)characteristic peaks,and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology,structure,and chemical composition.The decline in mechanical strength and thermal stability,and increased surface roughness and resistance negatively impacted fuel cell performance.At high current densities,the emergence of water flooding increased mass transfer resistance from 0.1Ωcm^(2)to 1.968Ωcm^(2),with a maximum power density decay rate reaching 71.17%.This study reveals the significant negative impact of Cr_(2)(SO_(4))_(3)contamination on GDL and fuel cell performance,highlighting that changes in surface structure,reduced hydrophobicity,and increased mass transfer resistance are primary causes of performance degradation.The findings provide crucial insights for improving GDL materials,optimizing fuel cell manufacturing and operation processes,and addressing contamination issues in practical applications.展开更多
All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocess...All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocessed CsPbIBr_(2) perovskite films with large thicknesses remains challenging.Here,we develop a triple-component precursor(TCP) by employing lead bromide,lead iodide,and cesium bromide,to replace the most commonly used double-component precursor(DCP) consisting of lead bromide and cesium iodide.Remarkably,the TCP system significantly increases the solution concentration to 1.3 M,leading to a larger film thickness(~390 nm) and enhanced light absorption.The resultant CsPbIBr_(2) films were evaluated in planar n-i-p structured solar cells,which exhibit a considerably higher optimal photocurrent density of 11.50 mA cm^(-2) in comparison to that of DCP-based devices(10.69 mA cm^(-2)).By adopting an organic surface passivator,the maximum device efficiency using TCP is further boosted to a record efficiency of 12.8% for CsPbIBr_(2) perovskite solar cells.展开更多
基金supported by the Natural Science Foundation of Henan Province(No.242300420021)the Major Science and Technology Projects of Henan Province(No.221100230200)+4 种基金the Open Fund of State Key Laboratory of Advanced Refractories(No.SKLAR202210)the Key Science and Technology Program of Henan Province(No.232102241020)the Undergraduate Innovation and Entrepreneurship Training Program of Henan Province(No.S202310464012)the Ph.D.Research Startup Foundation of Henan University of Science and Technology(No.400613480015)the Postdoctoral Research Startup Foundation of Henan University of Science and Technology(No.400613554001).
文摘Aqueous Zn-ion batteries(AZIBs)have been regarded as promising alternatives to Li-ion batteries due to their advantages,such as low cost,high safety,and environmental friendliness.However,AZIBs face significant challenges in limited stability and lifetime owing to zinc dendrite growth and serious side reactions caused by water molecules in the aqueous electrolyte during cycling.To address these issues,a new eutectic electrolyte based on Zn(ClO_(4))_(2)·6H_(2)O-N-methylacetamide(ZN)is proposed in this work.Compared with aqueous electrolyte,the ZN eutectic electrolyte containing organic N-methylacetamide could regulate the solvated structure of Zn^(2+),effectively suppressing zinc dendrite growth and side reactions.As a result,the Zn//NH4 V4 O10 full cell with the eutectic ZN-1-3 electrolyte demonstrates significantly enhanced cycling stability after 1000 cycles at 1 A g^(-1).Therefore,this study not only presents a new eutectic electrolyte for zinc-ion batteries but also provides a deep understanding of the influence of Zn^(2+)solvation structure on the cycle stability,contributing to the exploration of novel electrolytes for high-performance AZIBs.
基金Funded by National Natural Science Foundation of China(No.52108188)State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology)(No.SYSJJ2024-15)+3 种基金State Key Laboratory of Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University(No.SKLBT-2301)Opening Project of State Key Laboratory of Green Building Materials(No.2022GBM10)Open Research Fund of Key Laboratory of Engineering Materials of Ministry of Water Resources,China Institute of Water Resources and Hydropower Research(No.EMF202407)General Project of Science and Technology Plan of Beijing Municipal Commission of Education(No.KM202110005018)。
文摘This article investigated the factors and mechanisms that affected the workability and mechanical properties of cement paste incorporating nano-TiO_(2).The findings indicated that,for nano-TiO_(2)aqueous solution concentrations of 3%,6%,9%,and 12%,the optimal dispersion effect was achieved with an ultrasonic dispersion time of 20 minutes.Specifically,at a 6%nano-TiO_(2)content,both the workability and mechanical performance of the cement paste were enhanced.Furthermore,while nano-TiO_(2)did not alter the types of hydration products present in the cement paste,it did increase the amount of C-S-H gels.This enhancement was attributed to a higher number of nucleation sites for hydration products,which promoted hydration and reduced the porosity of the cement paste.
文摘Nano-scale CuF_(2) with superior electrochemical activity was successfully prepared by a mixed solvent co-precipitation method.The SEM and TEM analyses demonstrated that the methanol concentration had a pronounced effect on both the particle size and the extent of agglomeration.With the increase in methanol content,the particle size and agglomeration of CuF_(2) decreased first and then increased.When the volume ratio of methanol to deionized water was 1:1,the CuF_(2) particles exhibited the smallest size and the lowest degree of agglomeration.CuF_(2) synthesized with 50%methanol exhibited superior electrochemical performances with a voltage plateau above 3 V and a 1st discharge capacity of 525.8 mAh·g^(-1) at 0.01 C due to the synergistic influence of the particle size and dispersion.The analysis results using electrochemical impedance spectroscopy(EIS)and constant current intermittent titration technique(GITT)affirmed the addition of methanol was beneficial for promoting Li+diffusion and accelerating electrochemical reaction kinetics of CuF_(2).
基金supported by the Scientific Research Fund of Hunan Provincial Education Department,China(No.22B0741)。
文摘The electrochemical performance of layered O3-type NaCrO_(2)cathode material is significantly affected by the side reactions between NaCrO_(2)and electrolyte during sodium storage.A uniform Cr_(2)O_(3)coating layer was in situ constructed on the surface of NaCrO_(2)by controlling the excess ratio of sodium source.The structure,morphology,valence and electrochemical performance of the Cr_(2)O_(3)-coated NaCrO_(2)were characterized.The results indicate that the Cr_(2)O_(3)coating layer does not alter the crystal structure and morphology of NaCrO_(2),but effectively suppresses the side reactions between NaCrO_(2)and electrolyte,and improves the surface/interfacial stability of NaCrO_(2)material.The Cr_(2)O_(3)-coated NaCrO_(2)exhibits improved electrochemical performance with a capacity retention of 66.4%after 500 cycles at 10C.
基金supported by the National Natural Science Foundation of China(Nos.22408072 and 22208074)Hainan Province Science and Technology Special Fund(No.ZDYF2024GXJS300)Hainan Provincial Natural Science Foundation of China(No.222QN225)。
文摘Coating techniques are efficient routes to modify surface property of composite membranes for enhanced membrane separations.However,it remains challenge to deposit continuous inorganic layers on hollow fiber substrates.This study combines surface segregation with physical vapor deposition(PVD)to construct intensified TiO_(2)layers on polyether sulfone(PES)hollow fiber substrates.During membrane fabrication,polyethylene-polypropylene glycol(F127)is used as surface segregation agent in casting solution,which enables PES hollow fibers with abundant hydroxy groups,thus improving the compatibility between PES and vaporized TiO_(2).The obtained PES/F127@TiO_(2)membranes exhibit tight TiO_(2)layers with tunable thickness,high mechanical strength,narrowed pore size and enhanced hydrophilicity.Moreover,the optimized PES/F127@TiO_(2)membranes show competitive antifouling performances in water treatment,with a water permeability up to 97 L·m^(-2)·h^(-1)·bar^(-1)and bovine serum albumin(BSA)rejection of~99%.This work is expected to provide a material design idea to deposit functional layers on polymers for fortified performances.
文摘This work is devoted to the development of a low cost dimensionally stable anode with high oxygen evolution catalytic activity for practical applications.For this purpose,a Ti/SnO_(x)/MnO_(2) anode was fabricated through an innovative strategy involving Sn electrodeposition,oxidation,and MnO_(2)-layer preparation.The structure of the anode was characterized,and the oxygen evolution performance was evaluated in a H_(2)SO_(4) solution.The results show that compared with the Ti/SnO_(2)/MnO_(2) anode prepared by the conventional brushing-annealing process,the Ti/SnO_(x)/MnO_(2) anode fabricated through the innovative procedure exhibits a lower oxygen evolution potential and a nearly 40%longer accelerated lifespan.The superior oxygen evolution performance of the Ti/SnO_(x)/MnO_(2) anode is attributed to the distinctive SnO_(x) intermediate layer fabricated through Sn electrodeposition followed by oxidation,which indicates the great potential of the anode as a dimensionally stable anode for metal electrowinning and hydrogen production by electrolysis,etc.
基金supported by the National Natural Science Foundation of China(Nos.52073290 and 51927803)the Science Fund for Distinguished Young Scholars of Liaoning Province(No.2023JH6/100500004)the Shenyang Science and Technology Plan Project(No.23-407-3-23).
文摘Mg_(3)Bi_(2)-based flms are promising near-room-temperature thermoelectric materials for the development of fexible thermoelectric devices.However,the high hole concentration caused by the abundance of intrinsic Mg vacancies easily leads to deterioration of electrical properties,especially for p-type Mg_(3)Bi_(2) flm.And the optimization of thermal conductivity of the Mg_(3)Bi_(2)-based flms is barely investigated.In this work,we demonstrate the improved thermoelectric performances of p-type Mg_(3)Bi_(2) through Ag doping by magnetron sputtering.This doping successfully reduces the hole concentration and broadens the band gap of Mg_(3)Bi_(2),thus resulting in a peak power factor of 442μW m−1 K−2 at 525 K.At the same time,Ag doping-induced fuctuations in mass and microscopic strain efectively enhanced the phonon scattering to reduce the lattice thermal conductivity.Consequently,a maximum thermoelectric fgure of merit of 0.22 is achieved at 525 K.Its near-roomtemperature thermoelectric performances demonstrate superior performance compared to many Mg_(3)Bi_(2)-based flms.To further evaluate its potential for thermoelectric power generation,we fabricated a thermoelectric device using Ag-doped Mg_(3)Bi_(2) flms,which achieved a power density of 864μW cm⁻2 at 35 K temperature diference.This study presents an efective strategy for the advancement of Mg_(3)Bi_(2)-based flms for application in micro-thermoelectric devices.
基金supported by the National Science Foundation for Distinguished Young Scholars of China(Grant No.12425209)the National Natural Science Foundation of China(Grant No.U20A20390,11827803,12172034,11822201,62004056,62104058,62271269).
文摘Neuromorphic devices have shown great potential in simulating the function of biological neurons due to their efficient parallel information processing and low energy consumption.MXene-Ti_(3)C_(2)T_(x),an emerging twodimensional material,stands out as an ideal candidate for fabricating neuromorphic devices.Its exceptional electrical performance and robust mechanical properties make it an ideal choice for this purpose.This review aims to uncover the advantages and properties of MXene-Ti_(3)C_(2)T_(x)in neuromorphic devices and to promote its further development.Firstly,we categorize several core physical mechanisms present in MXene-Ti_(3)C_(2)T_(x)neuromorphic devices and summarize in detail the reasons for their formation.Then,this work systematically summarizes and classifies advanced techniques for the three main optimization pathways of MXene-Ti_(3)C_(2)T_(x),such as doping engineering,interface engineering,and structural engineering.Significantly,this work highlights innovative applications of MXene-Ti_(3)C_(2)T_(x)neuromorphic devices in cutting-edge computing paradigms,particularly near-sensor computing and in-sensor computing.Finally,this review carefully compiles a table that integrates almost all research results involving MXene-Ti_(3)C_(2)T_(x)neuromorphic devices and discusses the challenges,development prospects,and feasibility of MXene-Ti_(3)C_(2)T_(x)-based neuromorphic devices in practical applications,aiming to lay a solid theoretical foundation and provide technical support for further exploration and application of MXene-Ti_(3)C_(2)T_(x)in the field of neuromorphic devices.
基金supported by the Fundamental Research Funds for the Central Universities(No.2019ZDPY04).
文摘In this work,the TiO_(2)/Sb_(2)S_(3) nanorod arrays(NRAs)were synthesized through a two-stage hydrothermal route for photoelectrochemical(PEC)water splitting.The effect of annealing treatment in Ar ambience on the PEC activity of TiO_(2)/Sb_(2)S_(3) composite sample was investigated by electrochemical impedance analysis,including Nyquist and Mott-Schottky(M-S)plots.It was demonstrated that vacuum annealing could crystallize Sb_(2)S_(3) component and change its color from red to black,leading to an increment of photocurrent density from 1.9 A/m^(2) to 4.25 A/m^(2) at 0 V versus saturated calomel electrode(VSCE).The enhanced PEC performance was mainly attributed to the improved visible light absorption.Moreover,annealing treatment facilitated retarding the electron-hole recombination occurred at the solid/liquid interfaces.Our work might provide a novel strategy for enhancing the PEC performance of a semiconductor electrode.
基金Open Project of Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education),Shanghai Jiao Tong University,China(No.201301)ClassⅢPeak Discipline of Shanghai—Materials Science and Engineering(High-energy Beam Intelligent Processing and Green Manufacturing),China。
文摘To explore the effect of sulfur vacancies in transition metal sulfide on the electrochemical properties of anode materials,the graphene oxide(GO)and CoNi2S4 were used as the raw materials to synthesize the rGO_(10)−CoNi_(2)S_(4−x)composite electrode materials by the solvothermal method.The obtained rGO_(10)−CoNi_(2)S_(4−x)electrode materials with sulfur vacancies consist of nanoflakes and nanorods.The galvanostatic charge−discharge test of the rGO_(10)−CoNi_(2)S_(4−x)electrode materials shows a great specific capacitance of 3050.1 F/g at a current density of 1 A/g.Moreover,the electrode materials still remain rate capability retention of 86.1%when the current density increases from 1 to at 10 A/g.The rGO_(10)−CoNi_(2)S_(4−x)composite containing sulfur vacancies has higher specific capacitance and better rate capability in comparison to the pristine rGO−CoNi2S4 without containing sulfur defects.The optimized rGO_(10)−CoNi_(2)S_(4−x)composite electrode materials with sulfur vacancies exhibit outstanding cycle stability and rate performance.
文摘To evaluate the effects of solar greenhouse with different structure and CO2 enrichment on illumination and temperature performance of greenhouse and cucumber growth and development in the central region of Inner Mongolia, the research used traditional solar greenhouse （A） and blanket-inside solar greenhouse（B）, and set 4 treatments： AE （traditional solar greenhouse A with CO2 enrichment）, AN （traditional solar greenhouse A without CO2 enrichment）, BE （blanket-inside solar greenhouse B with CO2 enrichment） and BN （blanket-inside solar greenhouse B without CO2 enrichment）, to explore the influence of cucumber growth, photosynthetic property, quality and yield in different structure solar greenhouses with CO2 enrichment. The results showed that the illumination and temperature in blanket-inside solar greenhouse was superior to traditional solar greenhouse, and the average light intensity in blanket-inside solar greenhouse increased by 21.05%, compared with traditional solar greenhouse. Under the condition of same greenhouse structure, stem height ,average stem diameter, contents of soluble sugar, vitamin C, net photosynthetic rate and yield showed any significant difference between the treatments with CO2 enrichment or not. Under the condition of same CO2 concentration, BE cucumber average stem height, average stem diameter, contents of soluble sugar, net photosynthetic rate and yield in BE was higher than which in AE. Therefore, the optimization in structure of blanket-inside solar greenhouse remarkably improved illumination and temperature property, combining with CO2 enrichment as application technology, there was crucial significance to promote the greenhouse performance and improve the efficiency of greenhouse vegetable production.
基金supported by the Science and Technology Program of Guangzhou,China(No.202002020020)the National Natural Science Foundation of China(Nos.51808227,51878292)the Fundamental Research Funds for the Central Universities(No.2020ZYGXZR015)。
文摘Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction.Herein,a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis method.The as-prepared samples had a large specific surface area(up to 2512 m^(2)/g),a moderate-high N content(up to 4.82 at.%),and high population(55%)of ultra-micropores(<0.7 nm).Regulating the N content and ultra-microporosity led to efficient CO_(2)adsorption and separation.At ambient pressure,the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO_(2)uptake of 4.25 mmol/g at 25℃ and 6.57 mmol/g at 0℃.These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis,primarily due to the existence of ultra-micropores.The sample exhibited excellent CO_(2)/N_(2)selectivity at 25℃ owing to the abundant basic pyridinic and pyrrolic N species;and showed superior CO_(2)adsorption-desorption cycling performance,which was maintained at 97% after 10 cycles at 25℃.Moreover,petroleum coke-based microporous carbon,with a considerably high specific surface area and hierarchical pore structure,exhibited excellent electrochemical performance over the N-doped sample,maintaining a favorable specific capacitance of 233.25F/g at 0.5 A/g in 6 mol/L KOH aqueous electrolyte.This study provides insight into the influence of N-doping on the porous properties of petroleum coke-based carbon.Furthermore,the as-prepared carbons were found to be promising adsorbents for CO_(2)adsorption,CO_(2)/N_(2)separation and electrochemical application.
基金jointly supported by the Natural Science Foundations of China(No.22179020,12174057)Fujian Province’s“Young Eagle Program”Youth Top Talents Program。
文摘To meet the demand for high-performance LiCoO_(2) batteries,it is necessary to overcome challenges such as interface degradation and rapid capacity degradation caused by changes in bulk structure,especially under deep delithiation and high temperature conditions.The ion conductive coating layer of Li_(3)PO_(4) has been directly modified on the surface of LiCoO_(2) particles using magnetron sputtering method,significantly improving the lithium storage performance of LiCoO_(2)@Li_(3)PO_(4) composites.Compared to pure LiCoO_(2),the modified LiCoO_(2) sample exhibits obviously better cycle life and high-temperature performance.Especially,under the conditions of 2 and 1 C,the LiCoO_(2)@Li_(3)PO_(4) electrode delivers excellent cycling performance at high voltage of 4.5 V,with capacity retention rates of 89.7%and 75.7%at room temperature and high temperature of 45℃,being far greater than those of 12.3%and 29.1%for bare LiCoO_(2) electrodes.It is discovered that the Li_(3)PO_(4) coating layer not only effectively enhances interface compatibility and suppresses the irreversible phase transition of LiCoO_(2),but also further improves the Li^(+)transport kinetics and significantly reduces battery polarization,ultimately enabling the modified LiCoO_(2) electrode to exhibit excellent lithium storage performance and thermal safety characteristics under high voltage conditions.Thus,such effective modified strategy can undoubtedly provide an important academic inspiration for LiCoO_(2) implication.
基金financially supported by the Guangzhou Basic and Applied Basic Research Foundation,China(No.303523)。
文摘CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.
基金This work was financially supported by the National Science Foundation of China(Nos.22169007 and 22362011)the Science and Technology Major Project of Guangxi(No.AA19046001)+3 种基金the Open Research Fund of Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials(Nos.EMFM20201105 and EMFM20181119)the Characteristic Innovation Projects of Universities in Guangdong Province(No.2022KTSCX324)the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20190808173815205)the University Teachers'Characteristic Innovation Research Project(No.2021XJZZ11).
文摘Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in practice.In this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above challenges.Co doping can effectively widen layer spacing and reduce Li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side reactions.Therefore,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) coating.Its capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.
基金supported by the European Research Council,ERC project Liquid3D,grant number 101045072supported by the Foundation of Science and Technology(FCT)of Portugal through the CMU-Portugal project WoW(Reference No:45913).
文摘The demand for sustainable and stretchable thin-film printed batteries for bioelectronics,wearables,and e-textiles is rapidly increasing.Recently,we developed a fully 3D-printed soft-matter thin-film Ga-Ag_(2)O battery with 3R characteristics:resilient to mechanical strain,repairable after damage,and recyclable.This battery achieved a record-breaking areal capacity of 26.37 mAh cm-2,increasing to 30.32 mAh cm^(-2) after 10 cycles under 100%strain.This performance stems from the synergistic effects of gallium’s liquid metal properties and the styrene-isoprene-styrene polymer in the anode.Gallium’s high specific capacity(1153.2 mAh g^(-1)),deformability,and self-healing abilities,supported by its supercooled liquid phase,significantly enhance the battery’s resilience and efficiency.However,the cathode’s lower theoretical capacity,due to Ag_(2)O(231.31 mAh g^(-1)),remains a limitation.Traditional Ag_(2)O-carbon black-styrene-isoprene-styrene cathodes experience rapid capacity decay as only the surface area of the active materials interacts with the electrolyte.To overcome this,we designed a carbon-filled Ag_(2)O foam electrode using a sacrificial sugar template,increasing the effective surface area.This optimization enhanced ion-exchange efficiency,specific capacity,and cyclability,achieving a specific capacity of 221.16 mAh g^(-1).Consequently,the Ga-Ag_(2)O stretchable battery attained a record areal capacity of 40.91 mAh cm^(-2)—double that of nonfoam electrodes—and exhibited fivefold improved charge-discharge cycles.Using ultrastretchable Ag-EGaIn-styrene-isoprene-styrene and carbon black-styrene-isoprene-styrene current collectors,the battery’s specific capacity increased by 33%under 50%strain.Integrated into a soft-matter smart wristband for temperature monitoring,the battery demonstrated its promise for wearable electronics.
基金The University of Technology,specifically the Department of Electromechanical Engineering,provided invaluable assistance during the experimental work,for which the authors are quite grateful.
文摘Achieving broadband solar thermal absorption via dilute nanofluids is still a daunting challenge since the absorption peaks of common metal particles are usually located in the visible part of the radiation spectrum.This paper aims to present the results of experimental investigations on the thermal performance of heat pipe-type evacuated solar collectors.The experimented system consists of 15 tubes,providing the hot nanofluid to 100-L storage in a closed flow loop.The solar collector with a gross area of 2.1 m^(2)is part of the solar hot water test system located in Baghdad-Iraq.Al2O3 nanofluid at 0.5%volume concentration in water as working fluid was used in three flow rates of 3.3,6.6,and 10 L/min over two months,March and April.The experimental results indicated that maximum solar irradiation was 1070 and 1270 W/m^(2)in March and April,respectively.The maximum daily average of rate heat gain 11,270 and 12,040 W was recorded in March and April,respectively.In terms of the best operational flow rate,the system performs better at 3.3 L/min nanofluid flow rate.For the considered study period,the average monthly maximum energy efficiencies of the solar collector in March and April were 86%and 80%,respectively.
文摘Tin sulfide(SnS_(2))anodes have garnered significant attention within emerging energy storage technologies.However,the application of SnS_(2)is curtailed due to its inherent limitations,including poor cyclic stability and inevitable volumetric expansion upon cycling.This study reports the successful fabrication of an innovative SnS_(2)-based composite,featuring an eggshell-like structured nitrogen-doped carbon coating,referred to as SnS_(2)@NxC.This novel architecture,wherein SnS_(2)acts as the core encapsulated by a nitrogen-doped carbon shell,characterized by a void space between the shell and core,is crucial in mitigating volumetric expansion.This configuration contributes to maintaining the structural integrity of the composite materials,even under the stresses of continuous cycling.Nitrogen within the carbon matrix enhances conductivity and promotes the formation of a more robust and stable solid electrolyte interphase(SEI)layer.Experimental investigations have substantiated the electrochemical superiority of the SnS_(2)@NxC electrode,demonstrating a specific capacity of 701.8 mA·h·g^(-1)after 1000 cycles at 0.5 A·g^(-1)and maintaining a capacity of 597.2mA·h·g^(-1)after 400 cycles at a heightened current density of 2 A·g^(-1).These findings underscore the exceptional cyclic performance and durability of the SnS_(2)@NxC electrode.
基金funded by Key Laboratory of Energy Conversion and Storage Technology(Southern University of Science and Technology)Ministry of Education+1 种基金Guangdong Innovative and Entrepreneurial Research Team Program(grant No.2016ZT06N500)Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(grant No.2018B030322001).
文摘The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)contamination on the gas diffusion layer(GDL)and PEMFC performance,systematically analyzing the physicochemical property changes and their correlation with electrochemical performance.The results indicate that after post-treatment,the GDL surface exhibited exposed carbon fibers,cracks,and large pores in the microporous layer(MPL),with a noticeable detachment of PTFE.There was a marked reduction in C and F element signals,an increase in O element signals,deposition of Cr_(2)(SO_(4))_(3),formation of C=O and C=C bonds,appearance of Cr_(2)(SO_(4))_(3)characteristic peaks,and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology,structure,and chemical composition.The decline in mechanical strength and thermal stability,and increased surface roughness and resistance negatively impacted fuel cell performance.At high current densities,the emergence of water flooding increased mass transfer resistance from 0.1Ωcm^(2)to 1.968Ωcm^(2),with a maximum power density decay rate reaching 71.17%.This study reveals the significant negative impact of Cr_(2)(SO_(4))_(3)contamination on GDL and fuel cell performance,highlighting that changes in surface structure,reduced hydrophobicity,and increased mass transfer resistance are primary causes of performance degradation.The findings provide crucial insights for improving GDL materials,optimizing fuel cell manufacturing and operation processes,and addressing contamination issues in practical applications.
基金The authors acknowledge the financial support by the National Natural Science Foundation of China(52161145408 and 21975038)the Research and Innovation Team Project of Dalian University of Technology(DUT2022TB10)+2 种基金the Fundamental Research Funds for the Central Universities(DUT22QN213)the Innovation Technology Fund(MRP/040/21X)the Green Technology Fund(GTF202020164)for their financial support。
文摘All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocessed CsPbIBr_(2) perovskite films with large thicknesses remains challenging.Here,we develop a triple-component precursor(TCP) by employing lead bromide,lead iodide,and cesium bromide,to replace the most commonly used double-component precursor(DCP) consisting of lead bromide and cesium iodide.Remarkably,the TCP system significantly increases the solution concentration to 1.3 M,leading to a larger film thickness(~390 nm) and enhanced light absorption.The resultant CsPbIBr_(2) films were evaluated in planar n-i-p structured solar cells,which exhibit a considerably higher optimal photocurrent density of 11.50 mA cm^(-2) in comparison to that of DCP-based devices(10.69 mA cm^(-2)).By adopting an organic surface passivator,the maximum device efficiency using TCP is further boosted to a record efficiency of 12.8% for CsPbIBr_(2) perovskite solar cells.
