Photocatalysis offers a sustainable solution to two pressing global issues:greenhouse gas mitigation and clean energy generation.By harnessing light energy,photocatalytic processes enable water splitting for hydrogen ...Photocatalysis offers a sustainable solution to two pressing global issues:greenhouse gas mitigation and clean energy generation.By harnessing light energy,photocatalytic processes enable water splitting for hydrogen production and CO_(2) conversion into value-added products.Among the materials explored for photocatalysis,nickel-based photocatalysts have emerged as highly promising due to their low cost,abundance,stability,and efficiency.This review summarizes recent advancements in Ni-based photocatalysts,highlighting their role in improving photocatalytic performance by enhancing light absorption,charge separation,and reducing charge recombination.Key challenges and future directions for optimizing these materials are also discussed,offering insights into their potential for advancing clean energy technologies.展开更多
In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsion...In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsions,in Pickering emulsions,solid microparticles or nanoparticles that localize at the interface between liquids are used as stabilizers,instead of surfactants,to enhance the droplet lifetime.Furthermore,Pickering emulsions show higher stability,lower toxicity,and stimuli-responsiveness,compared with emulsions that are stabilized by surfactants.Therefore,they can be considered attractive components for various uses,such as photocatalysis and the preparation of new materials.Moreover,the nanoparticle morphology strongly influences Pickering emulsion stability as well as the potential utilization of such emulsions.Here,we review recent findings concerning Pickering emulsions,with a particular focus on how the nanoparticles morphology(i.e.,cube,ellipsoid,nanosheet,sphere,cylinder,rod,peanut)influences the type and stability of such emulsions,and their current applications in different fields such as antibacterial activity,protein recognition,catalysis,photocatalysis,and water purification.展开更多
This study proposes an advanced leaching method using organic acids to recover rare earth elements(REEs)from NdFeB permanent magnets from end-of-life computers hard disk drives(HDDs).The end-oflife HDDs were first dis...This study proposes an advanced leaching method using organic acids to recover rare earth elements(REEs)from NdFeB permanent magnets from end-of-life computers hard disk drives(HDDs).The end-oflife HDDs were first dismantled in order to recover NdFeB magnets,which were then thermally demagnetized at 350℃during 30 min before crushing in a ball mill under inert atmosphere.Scanning electron microscopy/energy dispersive X-ray spectroscopy(SEM/EDS)analyses performed on the NdFeB magnets show the heterogeneous structure containing the major matric phase Nd_(2)Fe_(14)B and the REEsrich phase containing Nd and Pr oxides.Additionally,X-ray diffraction(XRD)and Mossbauer spectroscopy(MS)analyses on the ground NdFeB magnet show that grinding NdFeB magnets under inert atmosphere helps to minimize its oxidation.Chemical analysis shows that the composition of the ground sample is Nd:22.8 wt%,Pr:3.3 wt%,Dy:1.2 wt%,Fe:62.6 wt%,Co:1.5 wt%,B:0.9 wt%,Ni:0.6 wt%.Diagrams of speciation and equilibrium phases(E_(h) vs.pH)were calculated to determine the predominance of the formed species in the REEs-organic acids systems.The influence of the organic acid type(acetic acid,formic acid,citric acid and tartaric acid),the acid concentration(10 vol%,up to saturation),and the solid/liquid(S/L)ratio(0.5%-10%)on NdFeB magnets leaching was investigated employing an optimal experimental design conceived by the statistical software JMP.Acetic acid(CH_(3)COOH)shows the highest leaching performance of REEs,allowing leaching yields over 90%for Nd,Dy and Pr in the acid concentration range of 1.6-10 mol/L and the S/L ratio range of 0.5%-5%at a temperature of 60℃.The results presented in this investigation suggest that REEs can be recovered from magnets of end-of-life HDDs using an eco-friendly method assisted by organic acids.展开更多
Direct recycling is a novel approach to overcoming the drawbacks of conventional lithium-ion battery(LIB)recycling processes and has gained considerable attention from the academic and industrial sectors in recent yea...Direct recycling is a novel approach to overcoming the drawbacks of conventional lithium-ion battery(LIB)recycling processes and has gained considerable attention from the academic and industrial sectors in recent years.The primary objective of directly recycling LIBs is to efficiently recover and restore the active electrode materials and other components in the solid phase while retaining electrochemical performance.This technology's advantages over traditional pyrometallurgy and hydrometallurgy are costeffectiveness,energy efficiency,and sustainability,and it preserves the material structure and morphology and can shorten the overall recycling path.This review extensively discusses the advancements in the direct recycling of LIBs,including battery sorting,pretreatment processes,separation of cathode and anode materials,and regeneration and quality enhancement of electrode materials.It encompasses various approaches to successfully regenerate high-value electrode materials and streamlining the recovery process without compromising their electrochemical properties.Furthermore,we highlight key challenges in direct recycling when scaled from lab to industries in four perspectives:(1)battery design,(2)disassembling,(3)electrode delamination,and(4)commercialization and sustainability.Based on these challenges and changing market trends,a few strategies are discussed to aid direct recycling efforts,such as binders,electrolyte selection,and alternative battery designs;and recent transitions and technological advancements in the battery industry are presented.展开更多
A cleaner and eco-friendly method was developed for the preparation of tetrakis(aminomethyl)calix-[4]-resorcinarene via a synthetic pathway of five steps starting from methylresorcinol. This alternative methodology is...A cleaner and eco-friendly method was developed for the preparation of tetrakis(aminomethyl)calix-[4]-resorcinarene via a synthetic pathway of five steps starting from methylresorcinol. This alternative methodology is firstly based on avoiding the use of CH2BrCl, which is a non-eco-friendly substance with high ozone depletion potential, and on replacing it by CH2Cl2 as a readily available reagent with much less dangerous effects. Secondly, this method engages acetone or CH2Cl2 as the solvent of the bromination step in the place of the very toxic CCl4, leading to tetrakis(bromomethyl)calix-[4]-resorcinarene. The brominated intermediate has been reacted with sodium azide in acetone instead of the high-boiling solvent DMSO to produce tetrakis(azidomethyl) calix-[4]-resorcinarene without the need of tedious purification. Lastly, this work reports an efficient hydrogenation method of the versatile azido adduct employing Pt/C (5%) as the catalyst for the preparation of the amino cavitand as an alternative route with high atom economy that can replace the classical methods used currently.展开更多
Water/ethyl acetate/ethanol is widely used as a“green”extractant system.We show that 2 different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a cosolvent of wa...Water/ethyl acetate/ethanol is widely used as a“green”extractant system.We show that 2 different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a cosolvent of water and ethyl acetate:centrifuge-induced criticality and centrifuge-induced emulsification.The expected composition profiles of samples after centrifugation can be represented by bent lines in a ternary phase diagram when gravitational energy is added to the free energy of mixing.The experimental equilibrium composition profiles behave qualitatively as expected and can be predicted using a phenomenological theory of mixing.The concentration gradients are small except near the critical point,as expected for small molecules.Nevertheless,they are usable when accompanied by temperature cycles.These findings open new possibilities of centrifugal separation,even if control is delicate during temperature cycles.These schemes are accessible even at relatively low centrifugation speed for molecules that float and sediment with apparent molar masses several hundred times larger than the molecular mass.展开更多
A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in ...A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available sesamol.Starting from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall yield.This synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting group.The pentacycle(±)-4 was obtained after 4 additional steps.The Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc removed.The last step was a Swern oxidation allowing the expected intramolecular condensation.展开更多
The chaotropic character of Keggin-type polyoxotungstate anions was evaluated with respect to their ability to bind toγ-cyclodextrin(γ-CD)by varying the global charge density of the nanometer-sized polyanion.
Since the past few years,Pu(V)has gained much attention due to its potential contribution to the environmental migration of actinides.However,the preparation of concentrated(up to mM)and pure Pu(V)solutions is quite d...Since the past few years,Pu(V)has gained much attention due to its potential contribution to the environmental migration of actinides.However,the preparation of concentrated(up to mM)and pure Pu(V)solutions is quite difficult and often hindered by its great instability towards disproportionation,thus limiting the accessibility to physical and chemical property data.This work describes the rapid and facile sonochemical preparation of relatively stable Pu(V)solutions in the millimolar range free from the admixtures of the other oxidation states of plutonium.The mechanism deals with the sonochemical reduction of Pu(VI)in weakly acidic perchloric solutions by using the in situ generated H_(2)O_(2),where the kinetics can be dramatically enhanced under high frequency ultrasound and an Ar/O_(2) atmosphere.The quasi-exclusive presence of the Pu(V)aqua ion in solution was evidenced by UV-vis absorption spectroscopy.The prepared solutions were found to be stable for more than one month which allowed the accurate XAFS and NMR investigations of Pu(V).EXAFS spectra revealed the presence of two trans dioxo PuvO bonds at 1.81Åand 4-6 equatorial Pu-Oeq interactions at 2.47Åcharacteristic of coordinated water molecules.The exact number of water molecules(N[Oeq(H_(2)O)]=4)was determined by simulating the EXAFS spectra of the PuO_(2)+aqua complexes using DFT calculations(geometry and the Debye-Waller factor)and comparing them with experimental signals.For the first time,the magnetic susceptibility of the pentavalent state of plutonium in aqueous solutions was also determined(χM=16.3×10^(-9) m^(3) mol^(-1) at 25℃)and the related Curie constant was estimated(C=6.896×10^(-6 )m^(3) K mol^(-1)).展开更多
文摘Photocatalysis offers a sustainable solution to two pressing global issues:greenhouse gas mitigation and clean energy generation.By harnessing light energy,photocatalytic processes enable water splitting for hydrogen production and CO_(2) conversion into value-added products.Among the materials explored for photocatalysis,nickel-based photocatalysts have emerged as highly promising due to their low cost,abundance,stability,and efficiency.This review summarizes recent advancements in Ni-based photocatalysts,highlighting their role in improving photocatalytic performance by enhancing light absorption,charge separation,and reducing charge recombination.Key challenges and future directions for optimizing these materials are also discussed,offering insights into their potential for advancing clean energy technologies.
文摘In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsions,in Pickering emulsions,solid microparticles or nanoparticles that localize at the interface between liquids are used as stabilizers,instead of surfactants,to enhance the droplet lifetime.Furthermore,Pickering emulsions show higher stability,lower toxicity,and stimuli-responsiveness,compared with emulsions that are stabilized by surfactants.Therefore,they can be considered attractive components for various uses,such as photocatalysis and the preparation of new materials.Moreover,the nanoparticle morphology strongly influences Pickering emulsion stability as well as the potential utilization of such emulsions.Here,we review recent findings concerning Pickering emulsions,with a particular focus on how the nanoparticles morphology(i.e.,cube,ellipsoid,nanosheet,sphere,cylinder,rod,peanut)influences the type and stability of such emulsions,and their current applications in different fields such as antibacterial activity,protein recognition,catalysis,photocatalysis,and water purification.
基金Project supported by the Occitanie region(RETREAt project-ALDOCT 000443)the French geological survey(BRGM)。
文摘This study proposes an advanced leaching method using organic acids to recover rare earth elements(REEs)from NdFeB permanent magnets from end-of-life computers hard disk drives(HDDs).The end-oflife HDDs were first dismantled in order to recover NdFeB magnets,which were then thermally demagnetized at 350℃during 30 min before crushing in a ball mill under inert atmosphere.Scanning electron microscopy/energy dispersive X-ray spectroscopy(SEM/EDS)analyses performed on the NdFeB magnets show the heterogeneous structure containing the major matric phase Nd_(2)Fe_(14)B and the REEsrich phase containing Nd and Pr oxides.Additionally,X-ray diffraction(XRD)and Mossbauer spectroscopy(MS)analyses on the ground NdFeB magnet show that grinding NdFeB magnets under inert atmosphere helps to minimize its oxidation.Chemical analysis shows that the composition of the ground sample is Nd:22.8 wt%,Pr:3.3 wt%,Dy:1.2 wt%,Fe:62.6 wt%,Co:1.5 wt%,B:0.9 wt%,Ni:0.6 wt%.Diagrams of speciation and equilibrium phases(E_(h) vs.pH)were calculated to determine the predominance of the formed species in the REEs-organic acids systems.The influence of the organic acid type(acetic acid,formic acid,citric acid and tartaric acid),the acid concentration(10 vol%,up to saturation),and the solid/liquid(S/L)ratio(0.5%-10%)on NdFeB magnets leaching was investigated employing an optimal experimental design conceived by the statistical software JMP.Acetic acid(CH_(3)COOH)shows the highest leaching performance of REEs,allowing leaching yields over 90%for Nd,Dy and Pr in the acid concentration range of 1.6-10 mol/L and the S/L ratio range of 0.5%-5%at a temperature of 60℃.The results presented in this investigation suggest that REEs can be recovered from magnets of end-of-life HDDs using an eco-friendly method assisted by organic acids.
基金National Research Foundation Singapore and National Environment Agency Singapore,Grant/Award Number:CTRL-2023-1D-01。
文摘Direct recycling is a novel approach to overcoming the drawbacks of conventional lithium-ion battery(LIB)recycling processes and has gained considerable attention from the academic and industrial sectors in recent years.The primary objective of directly recycling LIBs is to efficiently recover and restore the active electrode materials and other components in the solid phase while retaining electrochemical performance.This technology's advantages over traditional pyrometallurgy and hydrometallurgy are costeffectiveness,energy efficiency,and sustainability,and it preserves the material structure and morphology and can shorten the overall recycling path.This review extensively discusses the advancements in the direct recycling of LIBs,including battery sorting,pretreatment processes,separation of cathode and anode materials,and regeneration and quality enhancement of electrode materials.It encompasses various approaches to successfully regenerate high-value electrode materials and streamlining the recovery process without compromising their electrochemical properties.Furthermore,we highlight key challenges in direct recycling when scaled from lab to industries in four perspectives:(1)battery design,(2)disassembling,(3)electrode delamination,and(4)commercialization and sustainability.Based on these challenges and changing market trends,a few strategies are discussed to aid direct recycling efforts,such as binders,electrolyte selection,and alternative battery designs;and recent transitions and technological advancements in the battery industry are presented.
文摘A cleaner and eco-friendly method was developed for the preparation of tetrakis(aminomethyl)calix-[4]-resorcinarene via a synthetic pathway of five steps starting from methylresorcinol. This alternative methodology is firstly based on avoiding the use of CH2BrCl, which is a non-eco-friendly substance with high ozone depletion potential, and on replacing it by CH2Cl2 as a readily available reagent with much less dangerous effects. Secondly, this method engages acetone or CH2Cl2 as the solvent of the bromination step in the place of the very toxic CCl4, leading to tetrakis(bromomethyl)calix-[4]-resorcinarene. The brominated intermediate has been reacted with sodium azide in acetone instead of the high-boiling solvent DMSO to produce tetrakis(azidomethyl) calix-[4]-resorcinarene without the need of tedious purification. Lastly, this work reports an efficient hydrogenation method of the versatile azido adduct employing Pt/C (5%) as the catalyst for the preparation of the amino cavitand as an alternative route with high atom economy that can replace the classical methods used currently.
文摘Water/ethyl acetate/ethanol is widely used as a“green”extractant system.We show that 2 different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a cosolvent of water and ethyl acetate:centrifuge-induced criticality and centrifuge-induced emulsification.The expected composition profiles of samples after centrifugation can be represented by bent lines in a ternary phase diagram when gravitational energy is added to the free energy of mixing.The experimental equilibrium composition profiles behave qualitatively as expected and can be predicted using a phenomenological theory of mixing.The concentration gradients are small except near the critical point,as expected for small molecules.Nevertheless,they are usable when accompanied by temperature cycles.These findings open new possibilities of centrifugal separation,even if control is delicate during temperature cycles.These schemes are accessible even at relatively low centrifugation speed for molecules that float and sediment with apparent molar masses several hundred times larger than the molecular mass.
文摘A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available sesamol.Starting from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall yield.This synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting group.The pentacycle(±)-4 was obtained after 4 additional steps.The Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc removed.The last step was a Swern oxidation allowing the expected intramolecular condensation.
基金supported by a public grant overseen by the French National Research Agency as part of the“Investissements d’Avenir”program(Labex Charm3at,ANR-11-LABX-0039-grant)as well as the CNRS-MOMENTUMThis research is also supported by the China Scholarship Council(CSC)to S.Y.(201904910419).The authors are grateful to Flavien Bourdreux and Cyrielle Rey for their help with elemental analyses.
文摘The chaotropic character of Keggin-type polyoxotungstate anions was evaluated with respect to their ability to bind toγ-cyclodextrin(γ-CD)by varying the global charge density of the nanometer-sized polyanion.
文摘Since the past few years,Pu(V)has gained much attention due to its potential contribution to the environmental migration of actinides.However,the preparation of concentrated(up to mM)and pure Pu(V)solutions is quite difficult and often hindered by its great instability towards disproportionation,thus limiting the accessibility to physical and chemical property data.This work describes the rapid and facile sonochemical preparation of relatively stable Pu(V)solutions in the millimolar range free from the admixtures of the other oxidation states of plutonium.The mechanism deals with the sonochemical reduction of Pu(VI)in weakly acidic perchloric solutions by using the in situ generated H_(2)O_(2),where the kinetics can be dramatically enhanced under high frequency ultrasound and an Ar/O_(2) atmosphere.The quasi-exclusive presence of the Pu(V)aqua ion in solution was evidenced by UV-vis absorption spectroscopy.The prepared solutions were found to be stable for more than one month which allowed the accurate XAFS and NMR investigations of Pu(V).EXAFS spectra revealed the presence of two trans dioxo PuvO bonds at 1.81Åand 4-6 equatorial Pu-Oeq interactions at 2.47Åcharacteristic of coordinated water molecules.The exact number of water molecules(N[Oeq(H_(2)O)]=4)was determined by simulating the EXAFS spectra of the PuO_(2)+aqua complexes using DFT calculations(geometry and the Debye-Waller factor)and comparing them with experimental signals.For the first time,the magnetic susceptibility of the pentavalent state of plutonium in aqueous solutions was also determined(χM=16.3×10^(-9) m^(3) mol^(-1) at 25℃)and the related Curie constant was estimated(C=6.896×10^(-6 )m^(3) K mol^(-1)).
