A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li-ion batteries,as facile ionic transport is required.Intriguing research and developme...A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li-ion batteries,as facile ionic transport is required.Intriguing research and development have recently been conducted to form a stable interface between the electrode and electrolyte.Therefore,it is essential to investigate emerging knowledge and contextualize it.The nanoengineering of the electrode-electrolyte interface has been actively researched at the electrode/electrolyte and interphase levels.This review presents and summarizes some recent advances aimed at nanoengineering approaches to build a more stable electrode-electrolyte interface and assess the impact of each approach adopted.Furthermore,future perspectives on the feasibility and practicality of each approach will also be reviewed in detail.Finally,this review aids in projecting a more sustainable research pathway for a nanoengineered interphase design between electrode and electrolyte,which is pivotal for high-performance,thermally stable Li-ion batteries.展开更多
The demand for electronic devices that utilize lithium is steadily increasing in this rapidly advancing technological world.Obtaining high-purity lithium in an environmentally friendly way is challenging by using comm...The demand for electronic devices that utilize lithium is steadily increasing in this rapidly advancing technological world.Obtaining high-purity lithium in an environmentally friendly way is challenging by using commercialized methods.Herein,we propose the first fuel cell system for continuous lithium-ion extraction using a lithium superionic conductor membrane and advanced electrode.The fuel cell system for extracting lithium-ion has demonstrated a twofold increase in the selectivity of Li^(+)/Na^(+)while producing electricity.Our data show that the fuel cell with a titania-coated electrode achieves 95%lithium-ion purity while generating 10.23 Wh of energy per gram of lithium.Our investigation revealed that using atomic layer deposition improved the electrode's uniformity,stability,and electrocatalytic activity.After 2000 cycles determined by cyclic voltammetry,the electrode preserved its stability.展开更多
Owing to high electrical conductivity and ability to reversibly host a variety of inserted ions,2D metallic molybdenum disulfide(1 T-MoS_(2))has demonstrated promising energy storage performance when used as a superca...Owing to high electrical conductivity and ability to reversibly host a variety of inserted ions,2D metallic molybdenum disulfide(1 T-MoS_(2))has demonstrated promising energy storage performance when used as a supercapacitor electrode.However,its charge storage mechanism is still not fully understood,in particular,how the interlayer spacing of 1 T-MoS_(2)would affect its capacitive performance.In this work,molecular dynamics simulations of 1 T-MoS_(2)with interlayer spacing ranging from 0.615 to 1.615 nm have been performed to investigate the resulting charge storage capacity in ionic liquids.Simulations reveal a camel-like capacitance-potential relation,and MoS_(2)with an interlayer spacing of 1.115 nm has the highest volumetric and gravimetric capacitance of118 F cm^(-3)and 42 F g^(-1),respectively.Although ions in MoS_(2)with an interlayer spacing of 1.115 nm diffuse much faster than with interlayer spacings of 1.365 and 1.615 nm,the MoS_(2)with larger interlayer spacing has a much faster-charging process.Our analyses reveal that the ion number density and its charging speed,as well as ion motion paths,have significant impacts on the charging response.This work helps to understand how the interlayer spacing affects the interlayer ion structures and the capacitive performance of MoS_(2),which is important for revealing the charge storage mechanism and designing MoS_(2)supercapacitor.展开更多
Supercapacitors are highly valued energy storage devices with high power density,fast charging ability,and exceptional cycling stability.A profound understanding of their charging mechanisms is crucial for continuous ...Supercapacitors are highly valued energy storage devices with high power density,fast charging ability,and exceptional cycling stability.A profound understanding of their charging mechanisms is crucial for continuous performance enhancement.Electrochemical quartz crystal microbalance(EQCM),a detection means that provides in situ mass change information during charging–discharging processes at the nanogram level,has received greatly significant attention during the past decade due to its high sensitivity,non-destructiveness and low cost.Since being used to track ionic fluxes in porous carbons in 2009,EQCM has played a pivotal role in understanding the charging mechanisms of supercapacitors.Herein,we review the critical progress of EQCM hitherto,including theory fundamentals and applications in supercapacitors.Finally,we discuss the fundamental effects of ion desolvation and transport on the performance of supercapacitors.The advantages and defects of applying EQCM in supercapacitors are thoroughly examined,and future directions are proposed.展开更多
Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way...Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)2)·min^(-1)at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)2)at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.展开更多
Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influenc...Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.展开更多
P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in t...P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates.However,a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation.In this work,we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation.Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry,Na_(0.67)(Mn_(0.55)Ni_(0.21)Co_(0.24))O_(2),Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.24)Ti_(0.1)Mg_(0.03))O_(2) and Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.18)Ti_(0.1)Mg_(0.03)Al_(0.04)Fe_(0.02))O_(2) with low,medium and high configurational entropy,respectively.The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V.Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly.Overall,the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.展开更多
In the article titled“Three-Dimensional Cobalt Hydroxide Hollow Cube/Vertical Nanosheets with High Desalination Capacity and Long-Term Performance Stability in Capacitive Deionization”[1],there was an error in the t...In the article titled“Three-Dimensional Cobalt Hydroxide Hollow Cube/Vertical Nanosheets with High Desalination Capacity and Long-Term Performance Stability in Capacitive Deionization”[1],there was an error in the title.It previously read“Three-Dimensional Cobalt Hydroxide Hollow Cube/Vertical Nanosheets with High Desalinatio Capacity and Long-Term Performance Stability”,which was incorrect.The title in the original version has now been updated.展开更多
Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile proce...Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile process,adaptability for the broad concentration of feed water,and high selectivity.However,the adsorption method faces challenges in synthesizing highperformance sorbents and regenerating adsorbents effectively.FeOOH is an environmentally friendly sorbent with low-cost production on a large scale.Nevertheless,the selectivity behavior and regeneration of FeOOH are seldom studied.Therefore,we investigated the selectivity of FeOOH in a mixed solution of Co^(2+),Ni^(2+),and Pb^(2+)and proposed to enhance the capacity of FeOOH and regenerate it by using external charges.Without charge,the FeOOH electrode shows a Pb^(2+)uptake capacity of 20 mg/g.After applying a voltage of-0.2/+0.8 V,the uptake capacity increases to a maximum of 42 mg/g and the desorption ratio is 70%-80%.In 35 cycles,FeOOH shows a superior selectivity towards Pb^(2+)compared with Co^(2+)and Ni^(2+),with a purity of 97%±3%in the extracts.The high selectivity is attributed to the lower activation energy for Pb^(2+)sorption.The capacity retentions at the 5^(th)and the 35^(th)cycles are ca.80%and ca.50%,respectively,comparable to the chemical regeneration method.With industrially exhausted granular ferric hydroxide as the electrode material,the system exhibits a Pb^(2+)uptake capacity of 37.4 mg/g with high selectivity.Our work demonstrates the feasibility of regenerating FeOOH by charge and provides a new approach for recycling and upcycling FeOOH sorbent.展开更多
Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way...Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)_(2))·min^(-1) at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)_(2))at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.展开更多
基金supported by funding from Bavarian Center for Battery Technology(Baybatt,Hightech Agenda Bayern)and Bayerisch-Tschechische Hochschulagentur(BTHA)(BTHA-AP-202245,BTHA-AP-2023-5,and BTHA-AP-2023-12)supported by the University of Bayreuth-Deakin University Joint Ph.D.Program+1 种基金supported by the Regional Innovation Strategy(RIS)through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(2021RIS-003)supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS2023-00213749)
文摘A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li-ion batteries,as facile ionic transport is required.Intriguing research and development have recently been conducted to form a stable interface between the electrode and electrolyte.Therefore,it is essential to investigate emerging knowledge and contextualize it.The nanoengineering of the electrode-electrolyte interface has been actively researched at the electrode/electrolyte and interphase levels.This review presents and summarizes some recent advances aimed at nanoengineering approaches to build a more stable electrode-electrolyte interface and assess the impact of each approach adopted.Furthermore,future perspectives on the feasibility and practicality of each approach will also be reviewed in detail.Finally,this review aids in projecting a more sustainable research pathway for a nanoengineered interphase design between electrode and electrolyte,which is pivotal for high-performance,thermally stable Li-ion batteries.
文摘The demand for electronic devices that utilize lithium is steadily increasing in this rapidly advancing technological world.Obtaining high-purity lithium in an environmentally friendly way is challenging by using commercialized methods.Herein,we propose the first fuel cell system for continuous lithium-ion extraction using a lithium superionic conductor membrane and advanced electrode.The fuel cell system for extracting lithium-ion has demonstrated a twofold increase in the selectivity of Li^(+)/Na^(+)while producing electricity.Our data show that the fuel cell with a titania-coated electrode achieves 95%lithium-ion purity while generating 10.23 Wh of energy per gram of lithium.Our investigation revealed that using atomic layer deposition improved the electrode's uniformity,stability,and electrocatalytic activity.After 2000 cycles determined by cyclic voltammetry,the electrode preserved its stability.
基金the financial support from the National Natural Science Foundation of China(51876072)the Hubei Provincial Natural Science Foundation of China(2019CFA002,2020CFA093)+1 种基金Sichuan Science and Technology Program(2019YFG0457)the support from the National Energy Research Scientific Computing Center,a DOE Office of Science User Facility supported by the Office of Science of the U.S.Department of Energy under Contract No.DE-AC0205CH11231
文摘Owing to high electrical conductivity and ability to reversibly host a variety of inserted ions,2D metallic molybdenum disulfide(1 T-MoS_(2))has demonstrated promising energy storage performance when used as a supercapacitor electrode.However,its charge storage mechanism is still not fully understood,in particular,how the interlayer spacing of 1 T-MoS_(2)would affect its capacitive performance.In this work,molecular dynamics simulations of 1 T-MoS_(2)with interlayer spacing ranging from 0.615 to 1.615 nm have been performed to investigate the resulting charge storage capacity in ionic liquids.Simulations reveal a camel-like capacitance-potential relation,and MoS_(2)with an interlayer spacing of 1.115 nm has the highest volumetric and gravimetric capacitance of118 F cm^(-3)and 42 F g^(-1),respectively.Although ions in MoS_(2)with an interlayer spacing of 1.115 nm diffuse much faster than with interlayer spacings of 1.365 and 1.615 nm,the MoS_(2)with larger interlayer spacing has a much faster-charging process.Our analyses reveal that the ion number density and its charging speed,as well as ion motion paths,have significant impacts on the charging response.This work helps to understand how the interlayer spacing affects the interlayer ion structures and the capacitive performance of MoS_(2),which is important for revealing the charge storage mechanism and designing MoS_(2)supercapacitor.
基金the funding support from the National Natural Science Foundation of China(52161135104 and 52106090)Hubei Provincial Natural Science Foundation of China(2020CFA093)as well as the Program for HUST Academic Frontier Youth TeamM.C.also thanks to the Postdoctoral Creative Research Funding of Hubei Province.The INM authors thank Eduard Arzt(INM)for his continued support.
文摘Supercapacitors are highly valued energy storage devices with high power density,fast charging ability,and exceptional cycling stability.A profound understanding of their charging mechanisms is crucial for continuous performance enhancement.Electrochemical quartz crystal microbalance(EQCM),a detection means that provides in situ mass change information during charging–discharging processes at the nanogram level,has received greatly significant attention during the past decade due to its high sensitivity,non-destructiveness and low cost.Since being used to track ionic fluxes in porous carbons in 2009,EQCM has played a pivotal role in understanding the charging mechanisms of supercapacitors.Herein,we review the critical progress of EQCM hitherto,including theory fundamentals and applications in supercapacitors.Finally,we discuss the fundamental effects of ion desolvation and transport on the performance of supercapacitors.The advantages and defects of applying EQCM in supercapacitors are thoroughly examined,and future directions are proposed.
基金supported by the National Natural Science Foundation of China(52170087,21777118)the China Schol-arship Council(CSC)via award number 201906260277.
文摘Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)2)·min^(-1)at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)2)at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.
基金financial support by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)within the project MU 959/47-1Furthermore,the authors gratefully acknowledge funding in the ZuMat projectsupported by the State of Saarland from the European Regional Development Fund(Europäischer Fonds für Regionale Entwicklung,EFRE).P.Grützmacher and C.Gachot would like to thank the Government of Lower Austria(WST3)for financially supporting the endowed professorship tribology at the TU Wien.V.Presser thanks Eduard Arzt(INM)for his continuing support.
文摘Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.
基金financial support from the China Scholarship Council(CSC)financial support by Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy,EXC 2154,project number 390874152+8 种基金financial support from the Federal Ministry of Education and Research(Bundesministerium für Bildung und Forschung,BMBF)under the project‘KaSiLi’(03XP0254D)in the competence cluster‘Excell-BattMat’financial support from the Helmholtz Association(DigiBat project)support by the German Research Foundation(to H H,Grant No.HA 1344/43-1)is gratefully acknowledgedsupport from EnABLES and EPISTORE,projects funded by the European Union’s Horizon 2020 research and innovation program under Grant Agreement No.730957 and 101017709,respectivelyfunding from the Kera-Solar project(Carl Zeiss Foundation)support at beamline P65 of the PETRA Ⅲ synchrotron(Deutsches Elektronen-Synchrotron DESY,Hamburg,Germany)is gratefully acknowledgedEduard Arzt(INM)for his continuing supportAndrea Jung(INM)for her support on ICP-OES measurementsthe support from the Karlsruhe Nano Micro Facility(KNMF,www.knmf.kit.edu),a Helmholtz research infrastructure at Karlsruhe Institute of Technology(KIT,www.kit.du).
文摘P2-type layered oxides with the general Na-deficient composition Na_(x)TMO_(2)(x<1,TM:transition metal)are a promising class of cathode materials for sodium-ion batteries.The open Na+transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates.However,a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation.In this work,we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation.Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry,Na_(0.67)(Mn_(0.55)Ni_(0.21)Co_(0.24))O_(2),Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.24)Ti_(0.1)Mg_(0.03))O_(2) and Na_(0.67)(Mn_(0.45)Ni_(0.18)Co_(0.18)Ti_(0.1)Mg_(0.03)Al_(0.04)Fe_(0.02))O_(2) with low,medium and high configurational entropy,respectively.The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V.Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly.Overall,the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.
文摘In the article titled“Three-Dimensional Cobalt Hydroxide Hollow Cube/Vertical Nanosheets with High Desalination Capacity and Long-Term Performance Stability in Capacitive Deionization”[1],there was an error in the title.It previously read“Three-Dimensional Cobalt Hydroxide Hollow Cube/Vertical Nanosheets with High Desalinatio Capacity and Long-Term Performance Stability”,which was incorrect.The title in the original version has now been updated.
基金L.W.acknowledges funding from the Chinese Scholarship Council(CSC,No.201906260277)The work of L.D.was part of theÉcole Européenne d’Ingénieurs en Génie des Matériaux(EEIGM)carried out at Saarland University.Work at the Molecular Foundry was supported by the Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy(No.DE-AC02-05CH11231)We acknowledge support for the eLiRec project by the European Union from the European Regional Development Fund(EFRE)and the State of Saarland,Germany.S.J.Z.acknowledges support from Tulane University.
文摘Heavy metal pollution is a key environmental problem.Selectively extracting heavy metals could accomplish water purification and resource recycling simultaneously.Adsorption is a promising approach with a facile process,adaptability for the broad concentration of feed water,and high selectivity.However,the adsorption method faces challenges in synthesizing highperformance sorbents and regenerating adsorbents effectively.FeOOH is an environmentally friendly sorbent with low-cost production on a large scale.Nevertheless,the selectivity behavior and regeneration of FeOOH are seldom studied.Therefore,we investigated the selectivity of FeOOH in a mixed solution of Co^(2+),Ni^(2+),and Pb^(2+)and proposed to enhance the capacity of FeOOH and regenerate it by using external charges.Without charge,the FeOOH electrode shows a Pb^(2+)uptake capacity of 20 mg/g.After applying a voltage of-0.2/+0.8 V,the uptake capacity increases to a maximum of 42 mg/g and the desorption ratio is 70%-80%.In 35 cycles,FeOOH shows a superior selectivity towards Pb^(2+)compared with Co^(2+)and Ni^(2+),with a purity of 97%±3%in the extracts.The high selectivity is attributed to the lower activation energy for Pb^(2+)sorption.The capacity retentions at the 5^(th)and the 35^(th)cycles are ca.80%and ca.50%,respectively,comparable to the chemical regeneration method.With industrially exhausted granular ferric hydroxide as the electrode material,the system exhibits a Pb^(2+)uptake capacity of 37.4 mg/g with high selectivity.Our work demonstrates the feasibility of regenerating FeOOH by charge and provides a new approach for recycling and upcycling FeOOH sorbent.
基金supported by the National Natural Science Foundation of China(52170087,21777118)The INM authors thank Eduard Arzt(INM)for his continuing support.L.W.acknowledges funding from the China Scholarship Council(CSC)via award number 201906260277.
文摘Faradaic electrode materials have significantly improved the performance of membrane capacitive deionization,which offers an opportunity to produce freshwater from seawater or brackish water in an energy-efficient way.However,Faradaic materials hold the drawbacks of slow desalination rate due to the intrinsic low ion diffusion kinetics and inferior stability arising from the volume expansion during ion intercalation,impeding the engineering application of capacitive deionization.Herein,a pseudocapacitive material with hollow architecture was prepared via template-etching method,namely,cuboid cobalt hydroxide,with fast desalination rate(3.3 mg(NaCl)·g^(-1)(h-Co(OH)_(2))·min^(-1) at 100 mA·g^(-1))and outstanding stability(90%capacity retention after 100 cycles).The hollow structure enables swift ion transport inside the material and keeps the electrode intact by alleviating the stress induced from volume expansion during the ion capture process,which is corroborated well by in situ electrochemical dilatometry and finite element simulation.Additionally,benefiting from the elimination of unreacted bulk material and vertical cobalt hydroxide nanosheets on the exterior surface,the synthesized material provides a high desalination capacity(117±6 mg(NaCl)·g^(-1)(h-Co(OH)_(2))at 30 mA·g^(-1)).This work provides a new strategy,constructing microscale hollow faradic configuration,to further boost the desalination performance of Faradaic materials.