The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-...The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x),in situ grown on nickel foam(NF),holds great promise as a high-efficient bifunctional electrocatalyst(named R-CoFe/Ce/NF)for water splitting.Experimental characterization verifies surface reconstruction from CoFe alloy/oxide to highly active CoFeOOH during in situ electrochemical polarization.By virtues of three-dimensional nanoporous architecture and abundant electroactive CoFeOOH/CeO_(2−x) heterostructure interfaces,the R-CoFe/Ce/NF electrode achieves low overpotentials for oxygen evolution(η_(10)=227 mV;η_(500)=450 mV)and hydrogen evolution(η_(10)=35 mV;η_(408)=560 mV)reactions with high normalized electrochemical active surface areas,respectively.Additionally,the alkaline full water splitting electrolyzer of R-CoFe/Ce/NF||R-CoFe/Ce/NF achieves a current density of 50 mA·cm^(−2) only at 1.75 V;the decline of activity is satisfactory after 100-h durability test at 300 mA·cm^(−2).Density functional theory also demonstrates that the electron can transfer from CeO_(2−x) by virtue of O atom to CoFeOOH at CoFeOOH/CeO_(2−x) heterointerfaces and enhancing the adsorption of reactant,thus optimizing electronic structure and Gibbs free energies for the improvement of the activity for water splitting.展开更多
Although a new-class of heat pumps based on mechanically flexible nanoporous materials holds great poten-tial for the utilization of sustainable refrigerants with a considerably high coefficient of performance(COP),re...Although a new-class of heat pumps based on mechanically flexible nanoporous materials holds great poten-tial for the utilization of sustainable refrigerants with a considerably high coefficient of performance(COP),reducing their system volume remains a challenge.In this study,we explored the potential of this innovative type of heat pump in terms of COP and system volume.To broaden the scope of material exploration,we devised a new thermodynamic heat pump system applicable to soft mesoporous materials,in addition to the conventional system that is suitable only for flexible microporous materials.Several key factors have been identified through the comparison of various nanoporous materials and refrigerants.Our systematic investigation reveals that the combination of mechanically softer nanoporous materials with ammonia refrigerants can achieve a high COP and a reduced system volume.展开更多
Electrocatalytic conversion of carbon dioxide(CO_(2))into formate offers a sustainable pathway to mitigate environmental degradation and the energy crisis.Tin(Sn)-based materials are promising electrocatalysts for CO_...Electrocatalytic conversion of carbon dioxide(CO_(2))into formate offers a sustainable pathway to mitigate environmental degradation and the energy crisis.Tin(Sn)-based materials are promising electrocatalysts for CO_(2)reduction to formate;however,their efficiency is limited by weak CO_(2)adsorption and activation,as well as sluggish reaction kinetics.In this work,we designed an intercrossing nanoporous Cu_(6)Sn_(5)/Sn intermetallic heterojunction via a scalable alloying-etching protocol.The resulting Cu_(6)Sn_(5)/Sn catalyst with abundant interfacial sites exhibited enhanced formate selectivity(60.79%)at−0.93 V versus the reversible hydrogen electrode(RHE),together with a high partial current density of 12.56 mA/cm^(2)and stable operation for 16 h.The modulated electronic structure of Cu_(6)Sn_(5)coupled with the robust interfacial interaction between Sn and Cu_(6)Sn_(5)synergistically promoted CO_(2)adsorption and activation,thereby improving CO_(2)reduction reaction(CO_(2)RR)performance.Electrochemical measurements and in situ infrared spectroscopy confirmed that the dual-phase interfaces facilitate H_(2)O decomposition and the generation of abundant*H intermediates,which in turn accelerate the protonation of CO_(2)to formate.This work highlights a scalable strategy for constructing intermetallic heterojunction catalysts that combine facile synthesis,reproducibility,and superior catalytic activity for CO_(2)RR.展开更多
Using a combination of selective laser melting(SLM)and de-alloying methods,we prepared ultrafine crystalline nanoporous Cu.The resulting porous Cu exhibits grains ranging from 30-90 nm in size,pore sizes ranging from ...Using a combination of selective laser melting(SLM)and de-alloying methods,we prepared ultrafine crystalline nanoporous Cu.The resulting porous Cu exhibits grains ranging from 30-90 nm in size,pore sizes ranging from 50-300 nm,and a ligamentous structure with melt pool morphology.It is believed that the formation of ultrafine grains with nanoporous microstructures occurs due to the fast cooling rate of the melt pool,repeated heating during the printing process,and the intrinsic immiscibility of Cu and Fe.Our focus in this study lies on investigating the combined effects of parameters such as laser power,scanning speed,and scanning spacing on porous Cu precursors and porous Cu pore structures in the SLM technique,utilizing Taguchi's experimental method.The goal is to propose a design strategy for the rapid and high-precision fabrication of bulk ultrafine crystalline nanoporous metals.These metals hold promise for various functional applications and can be utilized in the preparation of porous metals across different systems.展开更多
Retaining satisfactory electrocatalytic performance under high current density plays a crucial role in industrial water splitting but is still limited to the enormous energy loss because of insufficient exposure of ac...Retaining satisfactory electrocatalytic performance under high current density plays a crucial role in industrial water splitting but is still limited to the enormous energy loss because of insufficient exposure of active sites caused by the blocked mass/charge transportation at this condition.Herein,we present a freestanding lamellar nanoporous Ni-Co-Mn alloy electrode(Lnp-NCM)designed by a refined variant of the“dealloying-coarsening-dealloying”protocol for highly efficient bifunctional electrocatalyst,where large porous channels distribute on the surface and small porous channels at the interlayer.With its 3D lamellar architecture regulating,the electrocatalytic properties of the electrodes with different distances between lamellas are compared,and faster energy conversion kinetics is achieved with efficient bubble transport channels and abundant electroactive sites.Note that the optimized sample(Lnp-NCM4)is expected to be a potential bifunctional electrocatalyst with low overpotentials of 258 and 439 mV at high current densities of 1000 and 900 mA·cm^(-2)for hydrogen and oxygen evolution reactions(HER and OER),respectively.During overall water splitting in a two-electrode cell with Lnp-NCM4 as cathode and anode,it only needs an ultralow cell voltage of 1.75 V to produce 100 mA·cm^(-2)with remarkable long-term stability over 50 h.This study on lamellar nanoporous electrode design approaches industrial water splitting requirements and paves a way for developing other catalytic systems.展开更多
In this work,we realized a room-temperature nitrogen dioxide(NO_(2))gas sensor based on a platinum(Pt)-loaded nanoporous gallium nitride(NP-GaN)sensing material using the thermal reduction method and coreduction with ...In this work,we realized a room-temperature nitrogen dioxide(NO_(2))gas sensor based on a platinum(Pt)-loaded nanoporous gallium nitride(NP-GaN)sensing material using the thermal reduction method and coreduction with the catalysis of polyols.The gas sensor gained excellent sensitivity to NO_(2) at a concentration range of 200 ppm to 100 ppb,benefiting from the loading of Pt nanoparticles,and exhibited a short response time(22 s)and recovery time(170 s)to 100 ppm of NO_(2) at room temperature with excellent selectivity to NO_(2) compared with other gases.This phenomenon was attributed to the spillover effect and the synergic electronic interaction with semiconductor materials of Pt,which not only provided more electrons for the adsorption of NO_(2) molecules but also occupied effective sites,causing poor sites for other gases.The low detection limit of Pt/NP-GaN was 100 ppb,and the gas sensor still had a fast response 70 d after fabrication.Besides,the gas-sensing mechanism of the gas sensor was further elaborated to determine the reason leading to its improved properties.The significant spillover impact and oxygen dissociation of Pt provided advantages to its synergic electronic interaction with semiconductor materials,leading to the improvement of the gas properties of gas sensors.展开更多
Intracellular electrophysiological research is vital for biological and medical research.Traditional planar microelectrode arrays(MEAs)have disadvantages in recording intracellular action potentials due to the loose c...Intracellular electrophysiological research is vital for biological and medical research.Traditional planar microelectrode arrays(MEAs)have disadvantages in recording intracellular action potentials due to the loose cell-electrode interface.To investigate intracellular electrophysiological signals with high sensitivity,electroporation was used to obtain intracellular recordings.In this study,a biosensing system based on a nanoporous electrode array(NPEA)integrating electrical perforation and signal acquisition was established to dynamically and sensitively record the intracellular potential of cardiomyocytes over a long period of time.Moreover,nanoporous electrodes can induce the protrusion of cell membranes and enhance cell-electrode interfacial coupling,thereby facilitating effective electroporation.Electrophysiological signals over the entire recording process can be quantitatively and segmentally analyzed according to the signal changes,which can equivalently reflect the dynamic evolution of the electroporated cardiomyocyte membrane.We believe that the low-cost and high-performance nanoporous biosensing platform suggested in this study can dynamically record intracellular action potential,evaluate cardiomyocyte electroporation,and provide a new strategy for investigating cardiology pharmacological science.展开更多
Bulk nanoporous(np)metallic actuators have attracted increasing attention due to their large strain and low stimulation voltage.However,studies focusing upon the combined effect of composition and structure on the act...Bulk nanoporous(np)metallic actuators have attracted increasing attention due to their large strain and low stimulation voltage.However,studies focusing upon the combined effect of composition and structure on the actuation performance of metallic actuators are relatively scarce,and its underlying mechanism needs to be clarified Herein,a series of bulk np-NiPd samples with differen compositions and microstructures were fabricated using a dealloying-coarsening-dealloying strategy and chargecontrolled electrochemical dealloying,and the process involves only one component of precursor alloy.It has been found that the np-NiPd cubes show a composition/structure-dependent mechanical property and electrochemical actuation performance.Specially,the npNi_(70)Pd_(30)sample with a homogeneously porous structure and good network connectivity exhibits significantly larger strain amplitude and faster strain rate than other hierarchically porous NiPd samples(np-Ni_(50)Pd_(50)and npNi_(20)Pd_(80)).Moreover,the np-Ni_(70)Pd_(30)sample demonstrates good actuation stability with high strain retention after hundreds of cycles.Notably,the maximum strain amplitude(1.17%)is even comparable to that of advanced leadfree piezoceramic,and the maximum strain rate exceeds those of many reported metallic actuator materials.Our work indicates that good network connectivity plays a vita role in facilitating large/fast strain response in metallic actuators.展开更多
Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional path...Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic devices.Indeed,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of NFRHT.In this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling ratio.The results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is 0.5.Moreover,the spectral heat flux exhibits redshift with increase in the vacuum filling ratio.To be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon polaritons.The introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon polaritons.These findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.展开更多
With high surface area,open porosity and high efficiency,a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate（DMC）.The electrochemical property...With high surface area,open porosity and high efficiency,a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate（DMC）.The electrochemical property for electrocatalytic reduction of CO2 in ionic liquid was studied by cyclic voltammogram（CV）.The effects of various reaction variables like temperature,working potential and cathode materials on the electrocatalytic performance were also investigated.80%yield of DMC was obtained under the optimal reaction conditions.展开更多
Oxidized nanoporous g-C3N4(PCNO)decorated with graphene oxide quantum dots(ox-GQDs)was successfully prepared by a facile self-assembly method.As co-catalysts,the ultrasmall zero-dimensional(0 D)ox-GQDs can achieve uni...Oxidized nanoporous g-C3N4(PCNO)decorated with graphene oxide quantum dots(ox-GQDs)was successfully prepared by a facile self-assembly method.As co-catalysts,the ultrasmall zero-dimensional(0 D)ox-GQDs can achieve uniform dispersion on the surface/inner channels of PCNO,as well as intimate contact with PCNO through hydrogen bonding,π-π,and chemical bonding interactions.In contrast with PCNO,the ox-GQDs/PCNO composite photocatalysts possessed improved light-harvesting ability,higher charge-transfer efficiency,enhanced photooxidation capacity,and increased amounts of reactive species due to the upconversion properties,strong electron capturing ability,and peroxidase-like activity of the ox-GQDs.Therefore,the visible-light photocatalytic degradation and disinfection performances of the ox-GQDs/PCNO composite were significantly enhanced.Remarkably,the composite with a 0.2 wt.% deposited amount of ox-GQDs(ox-GQDs-0.2%/PCNO)exhibited optimum amaranth photodegradation activity,with a corresponding rate about 3.1 times as high as that of PCNO.In addition,ox-GQDs-0.2%/PCNO could inactivate about 99.6%of Escherichia coli(E.coli)cells after 4 h of visible light irradiation,whereas only^31.9% of E.coli cells were killed by PCNO.Furthermore,h+,·O2-,and·OH were determined to be the reactive species generated in the photocatalytic process of the ox-GQDs/PCNO system;these species can thoroughly mineralize azo dyes and effectively inactivate pathogenic bacteria.展开更多
Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a...Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a wide range of current and future applications, and this is arguably one of the fastest growing research fields. In this review, we highlight various types of metal catalysts that possess great potential in several catalytic reactions. The major focus has been on metal oxides, nanoporous metals and metal NPs supported on metal-organic frameworks(MOFs) and zeolites. Special attention has been given to the synthesis strategies and application of the NPs supported on MOFs and zeolites, which are considered highly interesting and rapidly expanding areas in heterogeneous catalysis. Finally, the prospects of these catalysts have been included in the concluding remarks.展开更多
Metallic zinc(Zn)is one of the most attractive multivalent-metal anode materials in post-lithium batteries because of its high abundance,low cost and high theoretical capacity.However,it usually suffers from large vol...Metallic zinc(Zn)is one of the most attractive multivalent-metal anode materials in post-lithium batteries because of its high abundance,low cost and high theoretical capacity.However,it usually suffers from large voltage polarization,low Coulombic efficiency and high propensity for dendritic failure during Zn stripping/plating,hindering the practical application in aqueous rechargeable zinc-metal batteries(AR-ZMBs).Here we demonstrate that anionic surfactant-assisted in situ surface alloying of Cu and Zn remarkably improves Zn reversibility of 3D nanoporous Zn electrodes for potential use as high-performance AR-ZMB anode materials.As a result of the zincophilic ZnxCuy alloy shell guiding uniform Zn deposition with a zero nucleation overpotential and facilitating Zn stripping via the ZnxCuy/Zn galvanic couples,the self-supported nanoporous ZnxCuy/Zn electrodes exhibit superior dendrite-free Zn stripping/plating behaviors in ambient aqueous electrolyte,with ultralow polarizations under current densities up to 50 mA cm^(‒2),exceptional stability for 1900 h and high Zn utilization.This enables AR-ZMB full cells constructed with nanoporous ZnxCuy/Zn anode and K_(z)MnO_(2)cathode to achieve specific energy of as high as~430 Wh kg^(‒1)with~99.8%Coulombic efficiency,and retain~86%after long-term cycles for>700 h.展开更多
Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simpl...Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simple method to prepare three-dimensional self-supporting nanoporous materials without conductive supports and binders.In this work,we prepared self-supporting nanoporous CoBP electrocatalyst by dealloying method.The influence of the synergistic effect of nonmetallic elements on catalytic activity was investigated.The synergistic electronic effect of Co,B and P atoms on the surface optimizes the H atoms desorption and results in superior HER activity.The bi-continuous structure of nanoporous CoBP provides more active area and favors of electron and electrolyte transfer.The nanoporous CoBP with the B/P atomic ratio of 1/3 exhibits low overpotential of 42 mV at 10 mA·cm^(-2),small Tafel slope of 39.8 mV·dec-1 and good long-term stability with no performance decrease for 20 h in alkaline solution.展开更多
High entropy alloys(HEAs)containing five or more equimolar components have shown promising catalytic performance due to their unique chemical and mechanical properties.However,it is still challenging to prepare scalab...High entropy alloys(HEAs)containing five or more equimolar components have shown promising catalytic performance due to their unique chemical and mechanical properties.However,it is still challenging to prepare scalable and efficient nanoporous HEAs as catalysts.Here,we present a facile strategy to synthesize largescale nanoporous HEAs particles by combing vacuum induction melting,gas atomization,and acidic etching procedure.The application of HEAs to energy conversion is evaluated with electrocatalytic oxygen evolution reaction(OER)on AlCrCuFeNi HEAs.The HEAs exhibit a low OER overpotential of 270 mV to achieve a current density of 10 mA·cm^(-2),a small Tafel slope of 77.5 mV·dec^(-1),and long-term stability for over 35 h in 1 mol·L^(-1) KOH,which is comparable to the state-of-the-art OER electrocatalyst RuO2.The findings in this paper not only provide an industrial approach to produce nanoporous HEAs powder but also inspire the applications of HEAs as catalysts.展开更多
The humidity sensitive characteristics of the sensor fabricated from Ce-doped nanoporous ZnO by screen-printing on the alumina substrate with Ag-Pd interdigital electrodes were investigated at different sintering temp...The humidity sensitive characteristics of the sensor fabricated from Ce-doped nanoporous ZnO by screen-printing on the alumina substrate with Ag-Pd interdigital electrodes were investigated at different sintering temperatures.The nanoporous thin films were prepared by sol-gel technique.It was found that the impedance of the sensor sintered at 600 oC changed more than four order of magnitude in the relative humidity（RH） range of 11%-95% at 25 oC.The response and recovery time of the sensor were about 13 and 17 s,respectively.The sensor showed high humidity sensitivity,rapid response and recovery,prominent stability,good repeatability and narrow hysteresis loop.These re-sults indicated that Ce-doped nanoporous ZnO thin films can be used in fabricating high-performance humidity sensors.展开更多
In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its mater...In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its material structures. Herein, we report a simple strategy for high-performance supercapacitors by building pseudocapacitive CuS nanospheres with nanoporous structures, nanosized walls（<10 nm） and relatively large specific surface area of 65 m;/g. This electrode demonstrates excellent electrochemical performance including a maximum specific capacitance of 814 F/g at 1 A/g, significant rate capability of 42% capacitance retention at an ultrafast rate of 50 A/g, and outstanding long-term cycling stability at various current densities. The remarkable electrochemical performance of as-prepared nanoporous CuS nanospheres electrode has been attributed to its unique structures that plays a key role in providing short ion and electron diffusion pathways, facilitated ion transport and more active sites for electrochemical reactions. This work sheds a new light on the metal sulfides design philosophy, and demonstrates that nanoporous CuS nanospheres electrode is a promising candidate for application in high-performance supercapacitors.展开更多
Nanoporous BiVO;thin films were deposited using reactive magnetron sputtering in Ar and O;atmosphere, on various substrates, employing pulsed direct-current(DC) power supplies applied to metallic Bi and V targets for ...Nanoporous BiVO;thin films were deposited using reactive magnetron sputtering in Ar and O;atmosphere, on various substrates, employing pulsed direct-current(DC) power supplies applied to metallic Bi and V targets for rapid deposition. The procedure was followed by a post-annealing treatment in air to crystallize the photoactive monoclinic scheelite structure. The influence of total pressure and substrate on the crystal structure, morphology, microstructure, optical and photocatalytic properties of the films was investigated. The crystallization of monoclinic scheelite structure deposited on fused silica substrate starts at 250 ℃ and the films are stable up to 600 ℃. The morphology of the films is rather dense, despite at the high sputtering pressure(>2 Pa), with embedded nanopores. Among the thin films deposited on fused silica, the one deposited at 4.5 Pa exhibits the highest porosity(52%), with the lowest bandgap(2.44 eV) and it shows the highest photocatalytic activity in the degradation of Rhodamine-B(26% after 7 h) under visible light irradiation. The film deposited on the silicon substrate exhibits the highest photoactivity(53% after 7 h). Lack of hypsochromic shift in the UV-Vis temporal absorption spectra shows the dominance of the chromophore cleavage pathway in the photodecomposition.展开更多
Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step catalysis.Transmission electron microscope （TEM） and particle size analyzer were used to characterize the microstructur...Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step catalysis.Transmission electron microscope （TEM） and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy （SEM）, atomic force microscopy （AFM） and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.展开更多
Searching for free-standing and cost-efficient hydrogen evolution reaction(HER)electrocatalysts with high efficiency and excellent durability remains a great challenge for the hydrogen-based energy industry.Here,we re...Searching for free-standing and cost-efficient hydrogen evolution reaction(HER)electrocatalysts with high efficiency and excellent durability remains a great challenge for the hydrogen-based energy industry.Here,we report fabrication of a unique hierarchically porous structure,i.e.,nanoporous Ni(NPN)/metallic glass(MG)composite,through surface dealloying of the specially designed Ni_(40)Zr_(40)Ti_(20)MG wire.This porous composite is composed of micrometer slits staggered with nanometer pores,which not only enlarges effective surface areas for the catalytic reaction,but also facilitates the release of H2 gas.As a result,the NPN/MG hybrid electrode exhibited the prominent HER performance with a low overpotential of 78 m V at 10 m A cm^(-2)and Tafel slope of 42.4 m V dec^(-1),along with outstanding stability in alkaline solutions.Outstanding catalytic properties,combining with their free-standing capability and cost efficiency,make the current composite electrode viable for HER applications.展开更多
基金sponsored by the National Natural Science Foundation of China(Nos.5210125 and 52375422)the Science Research Project of Hebei Education Department(No.BJK2023058)the Natural Science Foundation of Hebei Province(Nos.E2020208069,B2020208083 and E202320801).
文摘The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x),in situ grown on nickel foam(NF),holds great promise as a high-efficient bifunctional electrocatalyst(named R-CoFe/Ce/NF)for water splitting.Experimental characterization verifies surface reconstruction from CoFe alloy/oxide to highly active CoFeOOH during in situ electrochemical polarization.By virtues of three-dimensional nanoporous architecture and abundant electroactive CoFeOOH/CeO_(2−x) heterostructure interfaces,the R-CoFe/Ce/NF electrode achieves low overpotentials for oxygen evolution(η_(10)=227 mV;η_(500)=450 mV)and hydrogen evolution(η_(10)=35 mV;η_(408)=560 mV)reactions with high normalized electrochemical active surface areas,respectively.Additionally,the alkaline full water splitting electrolyzer of R-CoFe/Ce/NF||R-CoFe/Ce/NF achieves a current density of 50 mA·cm^(−2) only at 1.75 V;the decline of activity is satisfactory after 100-h durability test at 300 mA·cm^(−2).Density functional theory also demonstrates that the electron can transfer from CeO_(2−x) by virtue of O atom to CoFeOOH at CoFeOOH/CeO_(2−x) heterointerfaces and enhancing the adsorption of reactant,thus optimizing electronic structure and Gibbs free energies for the improvement of the activity for water splitting.
文摘Although a new-class of heat pumps based on mechanically flexible nanoporous materials holds great poten-tial for the utilization of sustainable refrigerants with a considerably high coefficient of performance(COP),reducing their system volume remains a challenge.In this study,we explored the potential of this innovative type of heat pump in terms of COP and system volume.To broaden the scope of material exploration,we devised a new thermodynamic heat pump system applicable to soft mesoporous materials,in addition to the conventional system that is suitable only for flexible microporous materials.Several key factors have been identified through the comparison of various nanoporous materials and refrigerants.Our systematic investigation reveals that the combination of mechanically softer nanoporous materials with ammonia refrigerants can achieve a high COP and a reduced system volume.
基金supported by Natural Science Foundation of Shandong Province(No.ZR2023ME155)the project of“20 Items of University”of Jinan(No.202228046)the Tais-han Scholar Project of Shandong Province(Nos.tsqn202306226 and tsqn202211171).
文摘Electrocatalytic conversion of carbon dioxide(CO_(2))into formate offers a sustainable pathway to mitigate environmental degradation and the energy crisis.Tin(Sn)-based materials are promising electrocatalysts for CO_(2)reduction to formate;however,their efficiency is limited by weak CO_(2)adsorption and activation,as well as sluggish reaction kinetics.In this work,we designed an intercrossing nanoporous Cu_(6)Sn_(5)/Sn intermetallic heterojunction via a scalable alloying-etching protocol.The resulting Cu_(6)Sn_(5)/Sn catalyst with abundant interfacial sites exhibited enhanced formate selectivity(60.79%)at−0.93 V versus the reversible hydrogen electrode(RHE),together with a high partial current density of 12.56 mA/cm^(2)and stable operation for 16 h.The modulated electronic structure of Cu_(6)Sn_(5)coupled with the robust interfacial interaction between Sn and Cu_(6)Sn_(5)synergistically promoted CO_(2)adsorption and activation,thereby improving CO_(2)reduction reaction(CO_(2)RR)performance.Electrochemical measurements and in situ infrared spectroscopy confirmed that the dual-phase interfaces facilitate H_(2)O decomposition and the generation of abundant*H intermediates,which in turn accelerate the protonation of CO_(2)to formate.This work highlights a scalable strategy for constructing intermetallic heterojunction catalysts that combine facile synthesis,reproducibility,and superior catalytic activity for CO_(2)RR.
基金Funded by the Space Utilization System of China Manned Space Engineering(No.KJZ-YY-WCL03)the Guangd-ong Major Project of Basic and Applied Basic Research(No.2021B0301030001)+1 种基金the National Key Laboratory Foundation of Science and Technology on Materials under Shock and Impact(No.6142902210109)the Independent Innovation Projects of the Hubei Longzhong Laboratory(No.2022ZZ-32)。
文摘Using a combination of selective laser melting(SLM)and de-alloying methods,we prepared ultrafine crystalline nanoporous Cu.The resulting porous Cu exhibits grains ranging from 30-90 nm in size,pore sizes ranging from 50-300 nm,and a ligamentous structure with melt pool morphology.It is believed that the formation of ultrafine grains with nanoporous microstructures occurs due to the fast cooling rate of the melt pool,repeated heating during the printing process,and the intrinsic immiscibility of Cu and Fe.Our focus in this study lies on investigating the combined effects of parameters such as laser power,scanning speed,and scanning spacing on porous Cu precursors and porous Cu pore structures in the SLM technique,utilizing Taguchi's experimental method.The goal is to propose a design strategy for the rapid and high-precision fabrication of bulk ultrafine crystalline nanoporous metals.These metals hold promise for various functional applications and can be utilized in the preparation of porous metals across different systems.
基金supported by the National Natural Science Foundation of China(No.52101251)the Science Research Project of Hebei Education Department(No.BJK2023058)the Natural Science Foundation of Hebei Province(Nos.E2020208069 and B2020208083).
文摘Retaining satisfactory electrocatalytic performance under high current density plays a crucial role in industrial water splitting but is still limited to the enormous energy loss because of insufficient exposure of active sites caused by the blocked mass/charge transportation at this condition.Herein,we present a freestanding lamellar nanoporous Ni-Co-Mn alloy electrode(Lnp-NCM)designed by a refined variant of the“dealloying-coarsening-dealloying”protocol for highly efficient bifunctional electrocatalyst,where large porous channels distribute on the surface and small porous channels at the interlayer.With its 3D lamellar architecture regulating,the electrocatalytic properties of the electrodes with different distances between lamellas are compared,and faster energy conversion kinetics is achieved with efficient bubble transport channels and abundant electroactive sites.Note that the optimized sample(Lnp-NCM4)is expected to be a potential bifunctional electrocatalyst with low overpotentials of 258 and 439 mV at high current densities of 1000 and 900 mA·cm^(-2)for hydrogen and oxygen evolution reactions(HER and OER),respectively.During overall water splitting in a two-electrode cell with Lnp-NCM4 as cathode and anode,it only needs an ultralow cell voltage of 1.75 V to produce 100 mA·cm^(-2)with remarkable long-term stability over 50 h.This study on lamellar nanoporous electrode design approaches industrial water splitting requirements and paves a way for developing other catalytic systems.
基金supported by the National Natural Science Foundation of China(Nos.62031022 and 52375572)the Key R&D Program of Shanxi Province,China(No.202102030201003)+1 种基金Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,China(No.2022SXAT001)Key Core Technological Breakthrough Program of Taiyuan City,China(No.2024TYJB0126).
文摘In this work,we realized a room-temperature nitrogen dioxide(NO_(2))gas sensor based on a platinum(Pt)-loaded nanoporous gallium nitride(NP-GaN)sensing material using the thermal reduction method and coreduction with the catalysis of polyols.The gas sensor gained excellent sensitivity to NO_(2) at a concentration range of 200 ppm to 100 ppb,benefiting from the loading of Pt nanoparticles,and exhibited a short response time(22 s)and recovery time(170 s)to 100 ppm of NO_(2) at room temperature with excellent selectivity to NO_(2) compared with other gases.This phenomenon was attributed to the spillover effect and the synergic electronic interaction with semiconductor materials of Pt,which not only provided more electrons for the adsorption of NO_(2) molecules but also occupied effective sites,causing poor sites for other gases.The low detection limit of Pt/NP-GaN was 100 ppb,and the gas sensor still had a fast response 70 d after fabrication.Besides,the gas-sensing mechanism of the gas sensor was further elaborated to determine the reason leading to its improved properties.The significant spillover impact and oxygen dissociation of Pt provided advantages to its synergic electronic interaction with semiconductor materials,leading to the improvement of the gas properties of gas sensors.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LQ23E010004)the National Key Research and Development Program of China(No.2021YFB3200801)。
文摘Intracellular electrophysiological research is vital for biological and medical research.Traditional planar microelectrode arrays(MEAs)have disadvantages in recording intracellular action potentials due to the loose cell-electrode interface.To investigate intracellular electrophysiological signals with high sensitivity,electroporation was used to obtain intracellular recordings.In this study,a biosensing system based on a nanoporous electrode array(NPEA)integrating electrical perforation and signal acquisition was established to dynamically and sensitively record the intracellular potential of cardiomyocytes over a long period of time.Moreover,nanoporous electrodes can induce the protrusion of cell membranes and enhance cell-electrode interfacial coupling,thereby facilitating effective electroporation.Electrophysiological signals over the entire recording process can be quantitatively and segmentally analyzed according to the signal changes,which can equivalently reflect the dynamic evolution of the electroporated cardiomyocyte membrane.We believe that the low-cost and high-performance nanoporous biosensing platform suggested in this study can dynamically record intracellular action potential,evaluate cardiomyocyte electroporation,and provide a new strategy for investigating cardiology pharmacological science.
基金financially supported by the National Natural Science Foundation of China(Nos.U23A20554 and 52371158)the Key Research and Development Program of Shan dong Province(No.2021ZLGX01)+2 种基金Taishan Scholar Foundation of Shandong Province,the Natural Science Foundation of Shan dong Province(No.ZR2022QB169)the Excellent Youth Science Fund Project of Shan dong Province(Overseas)(No.2023HWYQ-018)the Postdoctoral Science foundation of China(No.2022M710077)。
文摘Bulk nanoporous(np)metallic actuators have attracted increasing attention due to their large strain and low stimulation voltage.However,studies focusing upon the combined effect of composition and structure on the actuation performance of metallic actuators are relatively scarce,and its underlying mechanism needs to be clarified Herein,a series of bulk np-NiPd samples with differen compositions and microstructures were fabricated using a dealloying-coarsening-dealloying strategy and chargecontrolled electrochemical dealloying,and the process involves only one component of precursor alloy.It has been found that the np-NiPd cubes show a composition/structure-dependent mechanical property and electrochemical actuation performance.Specially,the npNi_(70)Pd_(30)sample with a homogeneously porous structure and good network connectivity exhibits significantly larger strain amplitude and faster strain rate than other hierarchically porous NiPd samples(np-Ni_(50)Pd_(50)and npNi_(20)Pd_(80)).Moreover,the np-Ni_(70)Pd_(30)sample demonstrates good actuation stability with high strain retention after hundreds of cycles.Notably,the maximum strain amplitude(1.17%)is even comparable to that of advanced leadfree piezoceramic,and the maximum strain rate exceeds those of many reported metallic actuator materials.Our work indicates that good network connectivity plays a vita role in facilitating large/fast strain response in metallic actuators.
基金Project supported by the National Natural Science Foundation of China (Grant No.52106099)the Natural Science Foundation of Shandong Province (Grant No.ZR2022YQ57)the Taishan Scholars Program。
文摘Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field regime.Recent research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic devices.Indeed,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of NFRHT.In this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling ratio.The results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is 0.5.Moreover,the spectral heat flux exhibits redshift with increase in the vacuum filling ratio.To be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon polaritons.The introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon polaritons.These findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.
基金the National Natural Science Foundation of China(No.20976197) for its financial support of this project
文摘With high surface area,open porosity and high efficiency,a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate（DMC）.The electrochemical property for electrocatalytic reduction of CO2 in ionic liquid was studied by cyclic voltammogram（CV）.The effects of various reaction variables like temperature,working potential and cathode materials on the electrocatalytic performance were also investigated.80%yield of DMC was obtained under the optimal reaction conditions.
基金supported by the National Natural Science Foundation of China(21707052)Jiangsu Agriculture Science and Technology Innovation Fund(CX(18)2025)+1 种基金Fundamental Research Funds for the Central Universities(JUSRP11905 and JUSRP51714B)Key Research and Development Program of Jiangsu Province(BE2017623)~~
文摘Oxidized nanoporous g-C3N4(PCNO)decorated with graphene oxide quantum dots(ox-GQDs)was successfully prepared by a facile self-assembly method.As co-catalysts,the ultrasmall zero-dimensional(0 D)ox-GQDs can achieve uniform dispersion on the surface/inner channels of PCNO,as well as intimate contact with PCNO through hydrogen bonding,π-π,and chemical bonding interactions.In contrast with PCNO,the ox-GQDs/PCNO composite photocatalysts possessed improved light-harvesting ability,higher charge-transfer efficiency,enhanced photooxidation capacity,and increased amounts of reactive species due to the upconversion properties,strong electron capturing ability,and peroxidase-like activity of the ox-GQDs.Therefore,the visible-light photocatalytic degradation and disinfection performances of the ox-GQDs/PCNO composite were significantly enhanced.Remarkably,the composite with a 0.2 wt.% deposited amount of ox-GQDs(ox-GQDs-0.2%/PCNO)exhibited optimum amaranth photodegradation activity,with a corresponding rate about 3.1 times as high as that of PCNO.In addition,ox-GQDs-0.2%/PCNO could inactivate about 99.6%of Escherichia coli(E.coli)cells after 4 h of visible light irradiation,whereas only^31.9% of E.coli cells were killed by PCNO.Furthermore,h+,·O2-,and·OH were determined to be the reactive species generated in the photocatalytic process of the ox-GQDs/PCNO system;these species can thoroughly mineralize azo dyes and effectively inactivate pathogenic bacteria.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(Nos.NRF-2015R1A4A1041036 and NRF-2018R1C1B6006076)。
文摘Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a wide range of current and future applications, and this is arguably one of the fastest growing research fields. In this review, we highlight various types of metal catalysts that possess great potential in several catalytic reactions. The major focus has been on metal oxides, nanoporous metals and metal NPs supported on metal-organic frameworks(MOFs) and zeolites. Special attention has been given to the synthesis strategies and application of the NPs supported on MOFs and zeolites, which are considered highly interesting and rapidly expanding areas in heterogeneous catalysis. Finally, the prospects of these catalysts have been included in the concluding remarks.
基金supported by National Natural Science Foundation of China (No. 51871107, 52130101)Chang Jiang Scholar Program of China (Q2016064)+3 种基金the Program for JLU Science and Technology Innovative Research Team (JLUSTIRT, 2017TD-09)the Natural Science Foundation of Jilin Province (20200201019JC)the Fundamental Research Funds for the Central Universitiesthe Program for Innovative Research Team (in Science and Technology) in University of Jilin Province
文摘Metallic zinc(Zn)is one of the most attractive multivalent-metal anode materials in post-lithium batteries because of its high abundance,low cost and high theoretical capacity.However,it usually suffers from large voltage polarization,low Coulombic efficiency and high propensity for dendritic failure during Zn stripping/plating,hindering the practical application in aqueous rechargeable zinc-metal batteries(AR-ZMBs).Here we demonstrate that anionic surfactant-assisted in situ surface alloying of Cu and Zn remarkably improves Zn reversibility of 3D nanoporous Zn electrodes for potential use as high-performance AR-ZMB anode materials.As a result of the zincophilic ZnxCuy alloy shell guiding uniform Zn deposition with a zero nucleation overpotential and facilitating Zn stripping via the ZnxCuy/Zn galvanic couples,the self-supported nanoporous ZnxCuy/Zn electrodes exhibit superior dendrite-free Zn stripping/plating behaviors in ambient aqueous electrolyte,with ultralow polarizations under current densities up to 50 mA cm^(‒2),exceptional stability for 1900 h and high Zn utilization.This enables AR-ZMB full cells constructed with nanoporous ZnxCuy/Zn anode and K_(z)MnO_(2)cathode to achieve specific energy of as high as~430 Wh kg^(‒1)with~99.8%Coulombic efficiency,and retain~86%after long-term cycles for>700 h.
基金financially supported by the National Natural Science Foundation of China(No.51771131)。
文摘Water splitting is an environment friendly and efficient way to produce hydrogen.Highly efficient and low-cost non-noble metal catalysts play an important role in hydrogen evolution reaction(HER).Dealloying is a simple method to prepare three-dimensional self-supporting nanoporous materials without conductive supports and binders.In this work,we prepared self-supporting nanoporous CoBP electrocatalyst by dealloying method.The influence of the synergistic effect of nonmetallic elements on catalytic activity was investigated.The synergistic electronic effect of Co,B and P atoms on the surface optimizes the H atoms desorption and results in superior HER activity.The bi-continuous structure of nanoporous CoBP provides more active area and favors of electron and electrolyte transfer.The nanoporous CoBP with the B/P atomic ratio of 1/3 exhibits low overpotential of 42 mV at 10 mA·cm^(-2),small Tafel slope of 39.8 mV·dec-1 and good long-term stability with no performance decrease for 20 h in alkaline solution.
基金This study was financially supported by the National Natural Science Foundation of China(No.51771132).
文摘High entropy alloys(HEAs)containing five or more equimolar components have shown promising catalytic performance due to their unique chemical and mechanical properties.However,it is still challenging to prepare scalable and efficient nanoporous HEAs as catalysts.Here,we present a facile strategy to synthesize largescale nanoporous HEAs particles by combing vacuum induction melting,gas atomization,and acidic etching procedure.The application of HEAs to energy conversion is evaluated with electrocatalytic oxygen evolution reaction(OER)on AlCrCuFeNi HEAs.The HEAs exhibit a low OER overpotential of 270 mV to achieve a current density of 10 mA·cm^(-2),a small Tafel slope of 77.5 mV·dec^(-1),and long-term stability for over 35 h in 1 mol·L^(-1) KOH,which is comparable to the state-of-the-art OER electrocatalyst RuO2.The findings in this paper not only provide an industrial approach to produce nanoporous HEAs powder but also inspire the applications of HEAs as catalysts.
文摘The humidity sensitive characteristics of the sensor fabricated from Ce-doped nanoporous ZnO by screen-printing on the alumina substrate with Ag-Pd interdigital electrodes were investigated at different sintering temperatures.The nanoporous thin films were prepared by sol-gel technique.It was found that the impedance of the sensor sintered at 600 oC changed more than four order of magnitude in the relative humidity（RH） range of 11%-95% at 25 oC.The response and recovery time of the sensor were about 13 and 17 s,respectively.The sensor showed high humidity sensitivity,rapid response and recovery,prominent stability,good repeatability and narrow hysteresis loop.These re-sults indicated that Ce-doped nanoporous ZnO thin films can be used in fabricating high-performance humidity sensors.
文摘In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its material structures. Herein, we report a simple strategy for high-performance supercapacitors by building pseudocapacitive CuS nanospheres with nanoporous structures, nanosized walls（<10 nm） and relatively large specific surface area of 65 m;/g. This electrode demonstrates excellent electrochemical performance including a maximum specific capacitance of 814 F/g at 1 A/g, significant rate capability of 42% capacitance retention at an ultrafast rate of 50 A/g, and outstanding long-term cycling stability at various current densities. The remarkable electrochemical performance of as-prepared nanoporous CuS nanospheres electrode has been attributed to its unique structures that plays a key role in providing short ion and electron diffusion pathways, facilitated ion transport and more active sites for electrochemical reactions. This work sheds a new light on the metal sulfides design philosophy, and demonstrates that nanoporous CuS nanospheres electrode is a promising candidate for application in high-performance supercapacitors.
基金the supports of this study by the Iran National Science Foundation (No. 98001285)Pays de Montbéliard Agglomération (France) for the support of this work。
文摘Nanoporous BiVO;thin films were deposited using reactive magnetron sputtering in Ar and O;atmosphere, on various substrates, employing pulsed direct-current(DC) power supplies applied to metallic Bi and V targets for rapid deposition. The procedure was followed by a post-annealing treatment in air to crystallize the photoactive monoclinic scheelite structure. The influence of total pressure and substrate on the crystal structure, morphology, microstructure, optical and photocatalytic properties of the films was investigated. The crystallization of monoclinic scheelite structure deposited on fused silica substrate starts at 250 ℃ and the films are stable up to 600 ℃. The morphology of the films is rather dense, despite at the high sputtering pressure(>2 Pa), with embedded nanopores. Among the thin films deposited on fused silica, the one deposited at 4.5 Pa exhibits the highest porosity(52%), with the lowest bandgap(2.44 eV) and it shows the highest photocatalytic activity in the degradation of Rhodamine-B(26% after 7 h) under visible light irradiation. The film deposited on the silicon substrate exhibits the highest photoactivity(53% after 7 h). Lack of hypsochromic shift in the UV-Vis temporal absorption spectra shows the dominance of the chromophore cleavage pathway in the photodecomposition.
基金the National Natural Science Foundation of China(Grant No.20133040)the Chinese National Foundation of High Technology(2002AA842052)+1 种基金the Shanghai Nanotechnology Promotion Center(0352nm022,0352nm056)the Shanghai International Cooperation Program and Trans-Century Training Programme Foundation for the Talents by the State Education Commission.
文摘Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step catalysis.Transmission electron microscope （TEM） and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy （SEM）, atomic force microscopy （AFM） and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.
基金supported by National Natural Science Foundation of China(Nos.11790293,51871016,51671018,51671021,and 51961160729)the Funds for Creative Research Groups of China(No.51921001)+3 种基金111 Project(B07003)the Program for Changjiang Scholars and Innovative Research Team in University of China(IRT 14R05)the Fundamental Research Funds for the Central Universities(Nos.FRF-GF-19-011A,FRF-TP-18-004C1,FRF-BD-19-002B,and FRF-TP19-054A2)partially supported by State Key Laboratory for Advanced Metals and Materials(2018Z-19)。
文摘Searching for free-standing and cost-efficient hydrogen evolution reaction(HER)electrocatalysts with high efficiency and excellent durability remains a great challenge for the hydrogen-based energy industry.Here,we report fabrication of a unique hierarchically porous structure,i.e.,nanoporous Ni(NPN)/metallic glass(MG)composite,through surface dealloying of the specially designed Ni_(40)Zr_(40)Ti_(20)MG wire.This porous composite is composed of micrometer slits staggered with nanometer pores,which not only enlarges effective surface areas for the catalytic reaction,but also facilitates the release of H2 gas.As a result,the NPN/MG hybrid electrode exhibited the prominent HER performance with a low overpotential of 78 m V at 10 m A cm^(-2)and Tafel slope of 42.4 m V dec^(-1),along with outstanding stability in alkaline solutions.Outstanding catalytic properties,combining with their free-standing capability and cost efficiency,make the current composite electrode viable for HER applications.
