As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrog...As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.展开更多
Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treat...Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treatment are a key factor in determining the sodium-ion storage of pitchbased hard carbon anodes.We investigated the effects of the different molecular structures in the asphaltene precursor,including aromatic rings and aliphatic chains,on the sodiumion storage behavior of the resulting carbon.We found that polar oxygen functional groups limit the steric hindrance caused by the aromatic rings in pitch,and thus facilitate the introduction of cross-linked structures.During high-temperature carbonization,aromatic rings form a rigid carbon framework that prevents the rearrangement of ordered carbon layers,leading to a short-range disordered carbon structure and promotes the production of closed pores.For example,a material prepared from asphaltene,which contains a large number of oxygen-containing functional groups and macromolecular aromatic rings,using pre-oxidation at 300℃ and carbonization at 1200℃ had a reversible capacity of 316.7 mAh g^(−1) when used as the anode for sodium ion batteries.Our research provides a theoretical basis for the selection of raw materials for the development of high-quality pitch-based hard carbons.展开更多
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ...Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics.展开更多
Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Her...Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.展开更多
The pursuit of high energy density and sustainable energy storage devices has been the target of many researchers.However,safety issues such as the susceptibility of conventional liquid electrolytes to leakage and fla...The pursuit of high energy density and sustainable energy storage devices has been the target of many researchers.However,safety issues such as the susceptibility of conventional liquid electrolytes to leakage and flammability,as well as performance degradation due to uncontrollable dendrite growth in liquid electrolytes,have been limiting the further development of energy storage devices.In this regard,gel polymer electrolytes(GPEs)based on lignocellulosic(cellulose,hemicellulose,lignin)have attracted great interest due to their high thermal stability,excellent electrolyte wettability,and natural abundance.Therefore,in this critical review,a comprehensive overview of the current challenges faced by GPEs is presented,followed by a detailed description of the opportunities and advantages of lignocellulosic materials for the fabrication of GPEs for energy storage devices.Notably,the key properties and corresponding construction strategies of GPEs for energy storage are analyzed and discussed from the perspective of lignocellulose for the first time.Moreover,the future challenges and prospects of lignocellulose-mediated GPEs in energy storage applications are also critically reviewed and discussed.We sincerely hope this review will stimulate further research on lignocellulose-mediated GPEs in energy storage and provide meaningful directions for the strategy of designing advanced GPEs.展开更多
Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties intro...Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties introduce distinctive hydrodynamic phenomena in hydrogen storage,one of which is fingering.Fingering could induce the fluid trapped in small clusters of pores,leading to a dramatic decrease in hydrogen saturation and a lower recovery rate.In this study,numerical simulations are performed at the microscopic scale to understand the evolution of hydrogen saturation and the impacts of injection and withdrawal cycles.Two sets of micromodels with different porosity(0.362 and 0.426)and minimum sizes of pore throats(0.362 mm and 0.181 mm)are developed in the numerical model.A parameter analysis is then conducted to understand the influence of injection velocity(in the range of 10^(-2)m/s to 10^(-5)m/s)and porous structure on the fingering pattern,followed by an image analysis to capture the evolution of the fingering pattern.Viscous fingering,capillary fingering,and crossover fingering are observed and identified under different boundary conditions.The fractal dimension,specific area,mean angle,and entropy of fingers are proposed as geometric descriptors to characterize the shape of the fingering pattern.When porosity increases from 0.362 to 0.426,the saturation of hydrogen increases by 26.2%.Narrower pore throats elevate capillary resistance,which hinders fluid invasion.These results underscore the importance of pore structures and the interaction between viscous and capillary forces for hydrogen recovery efficiency.This work illuminates the influence of the pore structures and the fluid properties on the immiscible displacement of hydrogen and can be further extended to optimize the injection strategy of hydrogen in underground hydrogen storage.展开更多
Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summariz...Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summarizes recent advances in photo-assisted flexible energy storage technology,covering material design,working mechanisms,and practical applications.We systematically examine diverse electrode materials,such as metal oxides,metal sulfides,organic photosensitive materials,and composites,emphasizing their roles in boosting device performance.Special focus is placed on emerging technologies—including heterostructure engineering,surface modification,and intelligent control systems—that have notably enhanced energy conversion efficiency and storage capacity.The review also discusses current challenges,such as material stability,conversion efficiency,and standardization,and proposes strategic directions for future development.Recent breakthroughs in photo-assisted supercapacitors,lithium-based batteries,zinc-based batteries,and other innovative storage systems are critically assessed,offering key insights into their practical application potential in wearable electronics,self-powered sensors,and beyond.This comprehensive analysis establishes a framework for understanding the current status of photo-assisted flexible energy storage technology and guides future research toward high-performance,sustainable energy storage solutions.展开更多
Hard carbon(HC)remains a leading anode candidate for sodium-ion storage,yet its application is hindered by low initial Coulombic efficiency(ICE)and limited plateau capacity due to uncontrolled defect density and open ...Hard carbon(HC)remains a leading anode candidate for sodium-ion storage,yet its application is hindered by low initial Coulombic efficiency(ICE)and limited plateau capacity due to uncontrolled defect density and open porosity.Here,we propose a scalable dual-regulation strategy that simultaneously tunes pore mouth size and defect chemistry to enhance sodium storage performance.Using phenol-formaldehyde resin as the carbon precursor and phosphorus pentoxide(P2O5)as a bifunctional sacrificial template and dopant source,we synthesize phosphorus-functionalized hard carbon(PF-PHC)featuring a high density of closed pores with well-confined sub-nanometer pore entrances.The in-situ sublimation of P2O5 during pyrolysis promotes the formation of closed-pore architectures,while residual phosphorus atoms effectively passivate vacancy-type defects,thereby reducing irreversible Na+adsorption and mitigating excessive solid electrolyte interphase(SEI)formation.As a result,PF-PHC achieves an ICE of 89.3%and a plateau capacity of 289 mAh g−1.In-situ characterizations reveal that regulating pore mouth dimensions decouples Na+and solvent access,enabling highly selective ion transport and stable interfacial chemistry.Sodium-ion hybrid capacitors(SIHCs)assembled based on PF-PHC deliver exceptional rate performance and outstanding long-term cycling stability,retaining 98.2%after 10,000 cycles at 2 A g−1.This study establishes pore mouth engineering as a robust and scalable design principle for advancing next-generation HC-based sodium storage materials.展开更多
As renewable energy penetration continues to rise,enhancing power system flexibility has become a critical requirement.Photovoltaic–storage–charging stations(PSCSs)are key components for enhancing local regulation c...As renewable energy penetration continues to rise,enhancing power system flexibility has become a critical requirement.Photovoltaic–storage–charging stations(PSCSs)are key components for enhancing local regulation capability and promoting renewable integration.However,evaluating the adjustable capability of such hybrid stations while considering security constraints remains a major challenge.This paper first analyzes the adjustable capabilities of all the resources within such a station based on the power-energy boundary(PEB)model.Then,an optimal formulation is proposed to obtain the adjusted parameters of the aggregate feasible region(AFR)model,which embeds low-dimensional linear models within high-dimensional linear models to improve the accuracy.To solve this formulation,it is transformed using duality theory and an alternating optimization algorithm is designed to obtain the solution.Finally,a multi-station adjustable capability aggregation method considering security constraints is introduced.Simulation results verify that the proposed method effectively reduces infeasible regions and improves smoothness of aggregated boundaries,providing an accurate and practical tool for flexibility evaluation in PSCSs and offering guidance for aggregators and system planners.展开更多
In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)d...In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition.展开更多
In order to address environmental pollution and resource depletion caused by traditional power generation,this paper proposes an adaptive iterative dynamic-balance optimization algorithm that integrates the Improved D...In order to address environmental pollution and resource depletion caused by traditional power generation,this paper proposes an adaptive iterative dynamic-balance optimization algorithm that integrates the Improved Dung Beetle Optimizer(IDBO)with VariationalMode Decomposition(VMD).The IDBO-VMD method is designed to enhance the accuracy and efficiency of wind-speed time-series decomposition and to effectively smooth photovoltaic power fluctuations.This study innovatively improves the traditional variational mode decomposition(VMD)algorithm,and significantly improves the accuracy and adaptive ability of signal decomposition by IDBO selfoptimization of key parameters K and a.On this basis,Fourier transform technology is used to define the boundary point between high frequency and low frequency signals,and a targeted energy distribution strategy is proposed:high frequency fluctuations are allocated to supercapacitors to quickly respond to transient power fluctuations;Lowfrequency components are distributed to lead-carbon batteries,optimizing long-term energy storage and scheduling efficiency.This strategy effectively improves the response speed and stability of the energy storage system.The experimental results demonstrate that the IDBO-VMD algorithm markedly outperforms traditional methods in both decomposition accuracy and computational efficiency.Specifically,it effectively reduces the charge–discharge frequency of the battery,prolongs battery life,and optimizes the operating ranges of the state-of-charge(SOC)for both leadcarbon batteries and supercapacitors.In addition,the energy management strategy based on the algorithm not only improves the overall energy utilization efficiency of the system,but also shows excellent performance in the dynamic management and intelligent scheduling of renewable energy generation.展开更多
Achieving high energy and power densities is currently a core challenge in the fabrication of energy storage materials.Although numerous high-capacity materials have been developed,conventional planar electrodes canno...Achieving high energy and power densities is currently a core challenge in the fabrication of energy storage materials.Although numerous high-capacity materials have been developed,conventional planar electrodes cannot achieve high active material loading and efficient ion/electron transport simultaneously.By contrast,three-dimensional(3D)structures have attracted increasing interest because of their capacity to enhance active material utilization,shorten ion and electron transport pathways,reduce interfacial impedance,and provide spatial accommodation for volume expansion.Additive manufacturing(AM)technology effectively fabricates energy-storage materials with 3D structures by accurately constructing complex 3D structures via layer-by-layer deposition.Recent studies have employed AM to construct ordered 3D electrodes that can optimize ion/electron transport,regulate electric field distribution,or improve the electrode-electrolyte interface,thereby contributing to enhanced kinetic performance and cycling stability.This review systematically summarizes the applications of several AM technologies in the fabrication of energy storage materials and analyzes their respective advantages and limitations.Subsequently,the advantages of AM technology in the fabrication of energy storage materials and several major optimization strategies are comprehensively discussed.Finally,the major challenges and potential applications of AM technology in energy storage material optimization are discussed.展开更多
Facing the economic challenges of significant frequency regulation wear and tear on thermal power units and short energy storage lifespan in thermal-energy storage combined systems participating in grid primary freque...Facing the economic challenges of significant frequency regulation wear and tear on thermal power units and short energy storage lifespan in thermal-energy storage combined systems participating in grid primary frequency regulation(PFR),this paper proposes a novel hybrid energy storage system(HESS)control strategy based on Newton-Raphson optimization algorithm(NRBO)-VMD and a fuzzy neural network(FNN)for PFR.In the primary power allocation stage,the high inertia and slow response of thermal power units prevent them from promptly responding to the high-frequency components of PFR signals,leading to increased mechanical stress.To address the distinct response characteristics of thermal units and HESS,an NRBO-VMD based decomposition method for PFR signals is proposed,enabling a flexible system response to grid frequency deviations.Within the HESS,an adaptive coordinated control strategy and a State of Charge(SOC)self-recovery strategy are introduced.These strategies autonomously adjust the virtual inertia and droop coefficients based on the depth of frequency regulation and the real-time SOC.Furthermore,a FNN is constructed to perform secondary refinement of the internal power distribution within the HESS.Finally,simulations under various operational conditions demonstrate that the proposed strategy effectively mitigates frequent power adjustments of the thermal unit during PFR,adaptively achieves optimal power decomposition and distribution,maintains the flywheel energy storage’s SOC within an optimal range,and ensures the long-term stable operation of the HESS.展开更多
MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due...MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.展开更多
The sealing capacity of caprock is critical for preventing CO_(2)migration and ensuring the safety of geological storage.However,existing research lacks a comprehensive overview of its sealing mechanisms and failure r...The sealing capacity of caprock is critical for preventing CO_(2)migration and ensuring the safety of geological storage.However,existing research lacks a comprehensive overview of its sealing mechanisms and failure risks.Here,recent findings on caprock sealing mechanisms,its influencing factors,failure risks,and evaluation methods are summarized.The main results include the following:(i)Caprock sealing mechanisms include capillary,hydraulic,hydrocarbon concentration,and hydrate sealing.(ii)Capillary and hydrate sealing block fluid-phase CO_(2),hydrocarbon concentration sealing prevents diffusive CO_(2),and hydraulic sealing prevents fluid and water-soluble phases.(iii)The sealing capacity is influenced by the storage site,stratigraphic environment,and caprock properties,with breakthrough pressure ranked as follows:gypsum rock>salt rock>mudstone/shale>limestone>silty mudstone.(iv)Diffusion leakage occurs when the diffusion coefficients is less than 10^(-12)m^(2)/s,the seepage leakage ranges between 10^(-8)m^(2)/s and 10^(-12)m^(2)/s,and the fracture leakage is greater than 10^(-8)m^(2)/s.(v)Hydro-mechanical(HM)coupling mechanisms,including CO_(2)diffusion,breakthrough migration,uplift deformation,and fracture flow,are essential for leakage risk simulations.Future research should address sealing mechanisms under complex conditions,define leakage risk thresholds,optimize multiphysical coupling computations,and implement effective engineering solutions to mitigate leakage risk.展开更多
基金Supported by Design and Performance Study of High-flux Metal Hydride Reactor Based on the Bionic Optimization(2078262)the‘Four-Chain’Integration Project at the Qinchuangyuan Chief Platform(S2025-YF-ZDXM)。
文摘As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.
文摘Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treatment are a key factor in determining the sodium-ion storage of pitchbased hard carbon anodes.We investigated the effects of the different molecular structures in the asphaltene precursor,including aromatic rings and aliphatic chains,on the sodiumion storage behavior of the resulting carbon.We found that polar oxygen functional groups limit the steric hindrance caused by the aromatic rings in pitch,and thus facilitate the introduction of cross-linked structures.During high-temperature carbonization,aromatic rings form a rigid carbon framework that prevents the rearrangement of ordered carbon layers,leading to a short-range disordered carbon structure and promotes the production of closed pores.For example,a material prepared from asphaltene,which contains a large number of oxygen-containing functional groups and macromolecular aromatic rings,using pre-oxidation at 300℃ and carbonization at 1200℃ had a reversible capacity of 316.7 mAh g^(−1) when used as the anode for sodium ion batteries.Our research provides a theoretical basis for the selection of raw materials for the development of high-quality pitch-based hard carbons.
文摘Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics.
基金supported by the National Key R&D Program of China (No.2022YFB3803703)the National Natural Science Foundation of China (Nos.52071141,52271212,52201250,51771056,22305104)+1 种基金the Natural Science Foundation of Jiangsu Province (No.BK20210893)the Ministry of Science and Technology of the People’s Republic of China (No.G2023014022L)。
文摘Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.
基金supported by the National Natural Science Foundation of China(32501592,32271814,32301530,32471806)Young Elite Scientist Sponsorship Program by Cast(No.YESS20230242)+3 种基金Natural Science Foundation of Tianjin(23JCZDJC00630,24JCZDJC00630)the China Postdoctoral Science Foundation(2023M740563)Tianjin Enterprise Technology Commissioner Project(25YDTPJC00690)China Scholarship Council(202408120091,202408120105).
文摘The pursuit of high energy density and sustainable energy storage devices has been the target of many researchers.However,safety issues such as the susceptibility of conventional liquid electrolytes to leakage and flammability,as well as performance degradation due to uncontrollable dendrite growth in liquid electrolytes,have been limiting the further development of energy storage devices.In this regard,gel polymer electrolytes(GPEs)based on lignocellulosic(cellulose,hemicellulose,lignin)have attracted great interest due to their high thermal stability,excellent electrolyte wettability,and natural abundance.Therefore,in this critical review,a comprehensive overview of the current challenges faced by GPEs is presented,followed by a detailed description of the opportunities and advantages of lignocellulosic materials for the fabrication of GPEs for energy storage devices.Notably,the key properties and corresponding construction strategies of GPEs for energy storage are analyzed and discussed from the perspective of lignocellulose for the first time.Moreover,the future challenges and prospects of lignocellulose-mediated GPEs in energy storage applications are also critically reviewed and discussed.We sincerely hope this review will stimulate further research on lignocellulose-mediated GPEs in energy storage and provide meaningful directions for the strategy of designing advanced GPEs.
基金supported by the National Key Research and Development Project(Grant No.2023YFE0110900)the National Natural Science Foundation of China(Grant Nos.42320104003,42477168).
文摘Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties introduce distinctive hydrodynamic phenomena in hydrogen storage,one of which is fingering.Fingering could induce the fluid trapped in small clusters of pores,leading to a dramatic decrease in hydrogen saturation and a lower recovery rate.In this study,numerical simulations are performed at the microscopic scale to understand the evolution of hydrogen saturation and the impacts of injection and withdrawal cycles.Two sets of micromodels with different porosity(0.362 and 0.426)and minimum sizes of pore throats(0.362 mm and 0.181 mm)are developed in the numerical model.A parameter analysis is then conducted to understand the influence of injection velocity(in the range of 10^(-2)m/s to 10^(-5)m/s)and porous structure on the fingering pattern,followed by an image analysis to capture the evolution of the fingering pattern.Viscous fingering,capillary fingering,and crossover fingering are observed and identified under different boundary conditions.The fractal dimension,specific area,mean angle,and entropy of fingers are proposed as geometric descriptors to characterize the shape of the fingering pattern.When porosity increases from 0.362 to 0.426,the saturation of hydrogen increases by 26.2%.Narrower pore throats elevate capillary resistance,which hinders fluid invasion.These results underscore the importance of pore structures and the interaction between viscous and capillary forces for hydrogen recovery efficiency.This work illuminates the influence of the pore structures and the fluid properties on the immiscible displacement of hydrogen and can be further extended to optimize the injection strategy of hydrogen in underground hydrogen storage.
基金funded by the National Key Research and Development Program of China(2022YFB3807105)National Natural Science Foundation of China(52090033)+3 种基金State Key Laboratory for Modification of Chemical Fibers and Polymer Materials(KF222318)Jiangsu Province Industry-University-Research Cooperation Project(BY2022799)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX243534KYCX243521)。
文摘Photo-assisted flexible energy storage devices,combining photoelectric conversion and electrochemical energy storage,emerge as an innovative solution for sustainable energy systems.This review comprehensively summarizes recent advances in photo-assisted flexible energy storage technology,covering material design,working mechanisms,and practical applications.We systematically examine diverse electrode materials,such as metal oxides,metal sulfides,organic photosensitive materials,and composites,emphasizing their roles in boosting device performance.Special focus is placed on emerging technologies—including heterostructure engineering,surface modification,and intelligent control systems—that have notably enhanced energy conversion efficiency and storage capacity.The review also discusses current challenges,such as material stability,conversion efficiency,and standardization,and proposes strategic directions for future development.Recent breakthroughs in photo-assisted supercapacitors,lithium-based batteries,zinc-based batteries,and other innovative storage systems are critically assessed,offering key insights into their practical application potential in wearable electronics,self-powered sensors,and beyond.This comprehensive analysis establishes a framework for understanding the current status of photo-assisted flexible energy storage technology and guides future research toward high-performance,sustainable energy storage solutions.
基金supported by the National Natural Science Foundation of China(22269020,U23A20582,42167068)the Gansu Province Higher Education Industry Support Plan Project(2023CYZC-17)+1 种基金2024 Major Cultivation Project for University Research and Innovation Platforms(2024CXPT-10)the Key Project of the Natural Science Foundation of Gansu Province(25JRRA004).
文摘Hard carbon(HC)remains a leading anode candidate for sodium-ion storage,yet its application is hindered by low initial Coulombic efficiency(ICE)and limited plateau capacity due to uncontrolled defect density and open porosity.Here,we propose a scalable dual-regulation strategy that simultaneously tunes pore mouth size and defect chemistry to enhance sodium storage performance.Using phenol-formaldehyde resin as the carbon precursor and phosphorus pentoxide(P2O5)as a bifunctional sacrificial template and dopant source,we synthesize phosphorus-functionalized hard carbon(PF-PHC)featuring a high density of closed pores with well-confined sub-nanometer pore entrances.The in-situ sublimation of P2O5 during pyrolysis promotes the formation of closed-pore architectures,while residual phosphorus atoms effectively passivate vacancy-type defects,thereby reducing irreversible Na+adsorption and mitigating excessive solid electrolyte interphase(SEI)formation.As a result,PF-PHC achieves an ICE of 89.3%and a plateau capacity of 289 mAh g−1.In-situ characterizations reveal that regulating pore mouth dimensions decouples Na+and solvent access,enabling highly selective ion transport and stable interfacial chemistry.Sodium-ion hybrid capacitors(SIHCs)assembled based on PF-PHC deliver exceptional rate performance and outstanding long-term cycling stability,retaining 98.2%after 10,000 cycles at 2 A g−1.This study establishes pore mouth engineering as a robust and scalable design principle for advancing next-generation HC-based sodium storage materials.
基金supported by Science and Technology Project of China Southern Power Grid Company(036000KK52222007(GDKJXM20222121)).
文摘As renewable energy penetration continues to rise,enhancing power system flexibility has become a critical requirement.Photovoltaic–storage–charging stations(PSCSs)are key components for enhancing local regulation capability and promoting renewable integration.However,evaluating the adjustable capability of such hybrid stations while considering security constraints remains a major challenge.This paper first analyzes the adjustable capabilities of all the resources within such a station based on the power-energy boundary(PEB)model.Then,an optimal formulation is proposed to obtain the adjusted parameters of the aggregate feasible region(AFR)model,which embeds low-dimensional linear models within high-dimensional linear models to improve the accuracy.To solve this formulation,it is transformed using duality theory and an alternating optimization algorithm is designed to obtain the solution.Finally,a multi-station adjustable capability aggregation method considering security constraints is introduced.Simulation results verify that the proposed method effectively reduces infeasible regions and improves smoothness of aggregated boundaries,providing an accurate and practical tool for flexibility evaluation in PSCSs and offering guidance for aggregators and system planners.
基金funded by State Grid Corporation of China Central Branch Technology Project(52140024000C).
文摘In wind power transmission via modular multilevel converter based high voltage direct current(MMCHVDC)systems,under traditional control strategies,MMC-HVDCcannot provide inertia support to the receiving-end grid(REG)during disturbances.Moreover,due to the frequency decoupling between the two ends of the MMCHVDC,the sending-end wind farm(SEWF)cannot obtain the frequency variation information of the REG to provide inertia response.Therefore,this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system.First,the grid-side MMC station(GS-MMC)maps the frequency variations of the REG to direct current(DC)voltage variations through the frequency mapping control,and uses submodule capacitor energy to provide inertial power.Then,the wind farm-side MMC station(WF-MMC)restores the DC voltage variations to frequency variations through the frequency restoration control and power loss compensation,providing real-time frequency information for the wind farm.Finally,based on real-time frequency information,thewind farmutilizes the rotor kinetic energy and energy storage to provide fast and lasting power support through the wind-storage coordinated inertia control strategy.Meanwhile,when the wind turbines withdraw from the inertia response phase,the energy storage can increase the power output to compensate for the power deficit,preventing secondary frequency drops.Furthermore,this paper uses small-signal analysis to determine the appropriate values for the key parameters of the proposed control strategy.A simulation model of the wind power transmission via MMCHVDC system is built in MATLAB/Simulink environment to validate and evaluate the proposed method.The results show that the proposed coordinated control strategy can effectively improve the system inertia level and avoid the secondary frequency drop under the load sudden increase condition.
基金funded by the Institute of Smart Energy,Huaiyin Institute of Technology,under Grant No.HIT-ISE-2024-07.
文摘In order to address environmental pollution and resource depletion caused by traditional power generation,this paper proposes an adaptive iterative dynamic-balance optimization algorithm that integrates the Improved Dung Beetle Optimizer(IDBO)with VariationalMode Decomposition(VMD).The IDBO-VMD method is designed to enhance the accuracy and efficiency of wind-speed time-series decomposition and to effectively smooth photovoltaic power fluctuations.This study innovatively improves the traditional variational mode decomposition(VMD)algorithm,and significantly improves the accuracy and adaptive ability of signal decomposition by IDBO selfoptimization of key parameters K and a.On this basis,Fourier transform technology is used to define the boundary point between high frequency and low frequency signals,and a targeted energy distribution strategy is proposed:high frequency fluctuations are allocated to supercapacitors to quickly respond to transient power fluctuations;Lowfrequency components are distributed to lead-carbon batteries,optimizing long-term energy storage and scheduling efficiency.This strategy effectively improves the response speed and stability of the energy storage system.The experimental results demonstrate that the IDBO-VMD algorithm markedly outperforms traditional methods in both decomposition accuracy and computational efficiency.Specifically,it effectively reduces the charge–discharge frequency of the battery,prolongs battery life,and optimizes the operating ranges of the state-of-charge(SOC)for both leadcarbon batteries and supercapacitors.In addition,the energy management strategy based on the algorithm not only improves the overall energy utilization efficiency of the system,but also shows excellent performance in the dynamic management and intelligent scheduling of renewable energy generation.
基金support of the National Natural Science Foundation of China(No.52574411)Beijing Natural Science Foundation(No.2242043).
文摘Achieving high energy and power densities is currently a core challenge in the fabrication of energy storage materials.Although numerous high-capacity materials have been developed,conventional planar electrodes cannot achieve high active material loading and efficient ion/electron transport simultaneously.By contrast,three-dimensional(3D)structures have attracted increasing interest because of their capacity to enhance active material utilization,shorten ion and electron transport pathways,reduce interfacial impedance,and provide spatial accommodation for volume expansion.Additive manufacturing(AM)technology effectively fabricates energy-storage materials with 3D structures by accurately constructing complex 3D structures via layer-by-layer deposition.Recent studies have employed AM to construct ordered 3D electrodes that can optimize ion/electron transport,regulate electric field distribution,or improve the electrode-electrolyte interface,thereby contributing to enhanced kinetic performance and cycling stability.This review systematically summarizes the applications of several AM technologies in the fabrication of energy storage materials and analyzes their respective advantages and limitations.Subsequently,the advantages of AM technology in the fabrication of energy storage materials and several major optimization strategies are comprehensively discussed.Finally,the major challenges and potential applications of AM technology in energy storage material optimization are discussed.
基金supported by the Lanzhou Science and Technology Plan Project(XM1753694781389).
文摘Facing the economic challenges of significant frequency regulation wear and tear on thermal power units and short energy storage lifespan in thermal-energy storage combined systems participating in grid primary frequency regulation(PFR),this paper proposes a novel hybrid energy storage system(HESS)control strategy based on Newton-Raphson optimization algorithm(NRBO)-VMD and a fuzzy neural network(FNN)for PFR.In the primary power allocation stage,the high inertia and slow response of thermal power units prevent them from promptly responding to the high-frequency components of PFR signals,leading to increased mechanical stress.To address the distinct response characteristics of thermal units and HESS,an NRBO-VMD based decomposition method for PFR signals is proposed,enabling a flexible system response to grid frequency deviations.Within the HESS,an adaptive coordinated control strategy and a State of Charge(SOC)self-recovery strategy are introduced.These strategies autonomously adjust the virtual inertia and droop coefficients based on the depth of frequency regulation and the real-time SOC.Furthermore,a FNN is constructed to perform secondary refinement of the internal power distribution within the HESS.Finally,simulations under various operational conditions demonstrate that the proposed strategy effectively mitigates frequent power adjustments of the thermal unit during PFR,adaptively achieves optimal power decomposition and distribution,maintains the flywheel energy storage’s SOC within an optimal range,and ensures the long-term stable operation of the HESS.
基金supported by the National Natural Science Foundation of China(No.52302241 and 22225801)the Major Science and Technology Programs of Henan Province(241100240200)the China Postdoctoral Science Foundation(No.2023M730940).
文摘MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.
基金supported by the Joint Funds of the National Natural Science Foundation of China(Grant No.U23A20671)the Major Project of Inner Mongolia Science and Technology,China(Grant No.2021ZD0034)the Creative Groups of Natural Science Foundation of Hubei Province(Grant No.2021CFA030).
文摘The sealing capacity of caprock is critical for preventing CO_(2)migration and ensuring the safety of geological storage.However,existing research lacks a comprehensive overview of its sealing mechanisms and failure risks.Here,recent findings on caprock sealing mechanisms,its influencing factors,failure risks,and evaluation methods are summarized.The main results include the following:(i)Caprock sealing mechanisms include capillary,hydraulic,hydrocarbon concentration,and hydrate sealing.(ii)Capillary and hydrate sealing block fluid-phase CO_(2),hydrocarbon concentration sealing prevents diffusive CO_(2),and hydraulic sealing prevents fluid and water-soluble phases.(iii)The sealing capacity is influenced by the storage site,stratigraphic environment,and caprock properties,with breakthrough pressure ranked as follows:gypsum rock>salt rock>mudstone/shale>limestone>silty mudstone.(iv)Diffusion leakage occurs when the diffusion coefficients is less than 10^(-12)m^(2)/s,the seepage leakage ranges between 10^(-8)m^(2)/s and 10^(-12)m^(2)/s,and the fracture leakage is greater than 10^(-8)m^(2)/s.(v)Hydro-mechanical(HM)coupling mechanisms,including CO_(2)diffusion,breakthrough migration,uplift deformation,and fracture flow,are essential for leakage risk simulations.Future research should address sealing mechanisms under complex conditions,define leakage risk thresholds,optimize multiphysical coupling computations,and implement effective engineering solutions to mitigate leakage risk.
