Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt ...Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt oxyhydroxide @covalent organic frameworks(CoOOH@COFs) S-scheme heterojunction was synthesized,which combined the visible-light-driven photocatalysis and peroxymonosulfate(PMS) activation to synergistically generate abundant reactive oxygen species(ROSs) for TCS degradation.The degradation efficiency of TCS reached 100 % within 8 min in the Vis-CoOOH@COFs/PMS system,and the reaction rate constant was 0.456 min^(-1),which was nearly 1.90 and 2.85 times that of single Co OOH and COFs,and2.36 times that under dark condition,respectively.The density functional theory(DFT) calculations confirmed the energy band bending of CoOOH@COFs and S-scheme charge transport from COFs to Co OOH.Both experimental and theoretical analyses indicated that Co OOH@COFs in photocatalytic-PMS activation systems synergistically facilitated photo-generated carrier separation,enhanced interfacial electron transfer,accelerated PMS activation,and generated multiple ROSs.In particular,photogenerated electrons(e^(-))accelerated the Co(Ⅲ)/Co(Ⅱ) redox cycle,while the PMS captured the e-,which significantly decreased the charge combination of Co OOH@COFs.Radicals(O_(2)^(·-),^(·)OH,and SO_(4)^(·-)) and non-radicals(such as ^(1)O_(2),h^(+),and e^(-)) were both presented in the Vis-CoOOH@COFs/PMS system,with O_(2)^(-) playing a dominant role in TCS degradation.Furthermore,the pathway of TCS degradation and toxicity of intermediates were explored by DFT calculation and transformation product identification.Importantly,the environmentally friendly CoOOH@COFs S-scheme heterojunction exhibited excellent stability and reusability.In conclusion,this study innovatively designed an S-scheme heterojunction in the photocatalytic-PMS activation system,providing guidance and theoretical support for efficient and eco-friendly wastewater treatment.展开更多
Ascorbic acid（AA） serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA co...Ascorbic acid（AA） serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA content in different foods guides to build healthy diet, which is of great biomedical significance. Hence, developing a highly selective and instantaneous fluorescent nanoprobe for the detection of AA in biological samples is highly needed. Here we present a novel turn-on fluorescent nanoprobe using lanthanide-doped upconversion nanoparticles（UCNPs） and cobalt oxyhydroxide（Co OOH） nanoflakes for monitoring AA in fruit samples. In this nanosystem, the UCNPs can be adsorbed onto the Co OOH nanoflakes, leading to a remarkable fluorescence decrease through Fo？rster resonance energy transfer. Furthermore, the AA could trigger the disassembly of the Co OOH to liberate the upconverted fluorescence. The UCNPs-based nanoprobe can provide an effective platform for highly selective and rapid detection of AA in biological samples.展开更多
Lignin is the most promising candidate for producing aromatic compounds from biomass.However,the challenge lies in the cleavage of C-C bonds between lignin monomers under mild conditions,as these bonds have high disso...Lignin is the most promising candidate for producing aromatic compounds from biomass.However,the challenge lies in the cleavage of C-C bonds between lignin monomers under mild conditions,as these bonds have high dissociation energy.Electrochemical oxidation,which allows for mild cleavage of C-C bonds,is considered an attractive solution.To achieve low-energy consumption in the valorization of lignin,the use of highly efficient electrocatalysts is essential.In this study,a meticulously designed catalyst consisting of cobalt-doped nickel(oxy)hydroxide on molybdenum disulfide heterojunction was developed.The presence of molybdenum in a high valence state promoted the adsorption of tert-butyl hydroperoxide,leading to the formation of critical radical intermediates.In addition,the incorporation of cobalt doping regulated the electronic structure of nickel,resulting in a lower energy barrier.As a result,the heterojunction catalyst demonstrated a selectivity of 85.36% for cleaving the C_(α)-C_(β)bond in lignin model compound,achieving a substrate conversion of 93.69% under ambient conditions.In addition,the electrocatalyst depolymerized 49.82 wt% of soluble fractions from organosolv lignin(OL),resulting in a yield of up to 13 wt% of aromatic monomers.Significantly,the effectiveness of the prepared electrocatalyst was also demonstrated using industrial Kraft lignin(KL).Therefore,this research offers a practical approach for implementing electrocatalytic oxidation in lignin refining.展开更多
Cobalt oxyhydroxide(CoOOH)has been turned out to be a high-efficiency catalyst for peroxymonosulfate(PMS)activation.In this study,CoOOH was loaded on bismuth oxide(Bi_(2)O_(3))using a facile chemical precipitation pro...Cobalt oxyhydroxide(CoOOH)has been turned out to be a high-efficiency catalyst for peroxymonosulfate(PMS)activation.In this study,CoOOH was loaded on bismuth oxide(Bi_(2)O_(3))using a facile chemical precipitation process to improve its catalytic activity and stability.The result showed that the catalytic performance on the 2,4-dichlorophenol(2,4-DCP)degradation was significantly enhanced with only 11 wt%Bi_(2)O_(3)loading.The degradation rate in the CoOOH@Bi_(2)O_(3)/PMS system(0.2011 min−1)was nearly 6.0 times higher than that in the CoOOH/PMS system(0.0337 min−1).Furthermore,CoOOH@Bi_(2)O_(3)displayed better stability with less Co ions leaching(16.4%lower than CoOOH)in the PMS system.These phenomena were attributed to the Bi_(2)O_(3)loading which significantly increased the conductivity and specific surface area of the CoOOH@Bi_(2)O_(3)composite.Faster electron transfer facilitated the redox reaction of Co(III)/Co(II)and thus was more favorable for reactive oxygen species(ROS)generation.Meanwhile,larger specific surface area furnished more active sites for PMS activation.More importantly,there were both non-radical(^(1)O_(2))and radicals(SO_(4)^(−)•,O_(2)^(−)•,and OH•)in the CoOOH@Bi_(2)O_(3)/PMS system and^(1)O_(2)was the dominant one.In general,this study provided a simple and practical strategy to enhance the catalytic activity and stability of cobalt oxyhydroxide in the PMS system.展开更多
文摘Triclosan(TCS) poses harmful risks to ecosystems and human health owing to its endocrine-disrupting effects.Therefore,developing an efficient and sustainable technology to degrade TCS is urgently needed.Herein,cobalt oxyhydroxide @covalent organic frameworks(CoOOH@COFs) S-scheme heterojunction was synthesized,which combined the visible-light-driven photocatalysis and peroxymonosulfate(PMS) activation to synergistically generate abundant reactive oxygen species(ROSs) for TCS degradation.The degradation efficiency of TCS reached 100 % within 8 min in the Vis-CoOOH@COFs/PMS system,and the reaction rate constant was 0.456 min^(-1),which was nearly 1.90 and 2.85 times that of single Co OOH and COFs,and2.36 times that under dark condition,respectively.The density functional theory(DFT) calculations confirmed the energy band bending of CoOOH@COFs and S-scheme charge transport from COFs to Co OOH.Both experimental and theoretical analyses indicated that Co OOH@COFs in photocatalytic-PMS activation systems synergistically facilitated photo-generated carrier separation,enhanced interfacial electron transfer,accelerated PMS activation,and generated multiple ROSs.In particular,photogenerated electrons(e^(-))accelerated the Co(Ⅲ)/Co(Ⅱ) redox cycle,while the PMS captured the e-,which significantly decreased the charge combination of Co OOH@COFs.Radicals(O_(2)^(·-),^(·)OH,and SO_(4)^(·-)) and non-radicals(such as ^(1)O_(2),h^(+),and e^(-)) were both presented in the Vis-CoOOH@COFs/PMS system,with O_(2)^(-) playing a dominant role in TCS degradation.Furthermore,the pathway of TCS degradation and toxicity of intermediates were explored by DFT calculation and transformation product identification.Importantly,the environmentally friendly CoOOH@COFs S-scheme heterojunction exhibited excellent stability and reusability.In conclusion,this study innovatively designed an S-scheme heterojunction in the photocatalytic-PMS activation system,providing guidance and theoretical support for efficient and eco-friendly wastewater treatment.
基金supported by 973 Program (No. 2013CB933800) National Natural Science Foundation of China (Nos. 21390411, 21535004, 21422505, 21375081)Natural Science Foundation for Distinguished Young Scholars of Shandong Province (No. JQ201503)
文摘Ascorbic acid（AA） serves as a key coenzyme in many metabolic pathways. Enough daily AA supplements from different dietary sources are the only way for human to maintain their AA levels in body.Determination of AA content in different foods guides to build healthy diet, which is of great biomedical significance. Hence, developing a highly selective and instantaneous fluorescent nanoprobe for the detection of AA in biological samples is highly needed. Here we present a novel turn-on fluorescent nanoprobe using lanthanide-doped upconversion nanoparticles（UCNPs） and cobalt oxyhydroxide（Co OOH） nanoflakes for monitoring AA in fruit samples. In this nanosystem, the UCNPs can be adsorbed onto the Co OOH nanoflakes, leading to a remarkable fluorescence decrease through Fo？rster resonance energy transfer. Furthermore, the AA could trigger the disassembly of the Co OOH to liberate the upconverted fluorescence. The UCNPs-based nanoprobe can provide an effective platform for highly selective and rapid detection of AA in biological samples.
基金supported by the National Science Fund for Distinguished Young Scholars(grant no.31925028)the National Natural Science Foundation of China(grant no.22102019)the Natural Science Foundation of Heilongjiang Province(no.YQ2021C005).
文摘Lignin is the most promising candidate for producing aromatic compounds from biomass.However,the challenge lies in the cleavage of C-C bonds between lignin monomers under mild conditions,as these bonds have high dissociation energy.Electrochemical oxidation,which allows for mild cleavage of C-C bonds,is considered an attractive solution.To achieve low-energy consumption in the valorization of lignin,the use of highly efficient electrocatalysts is essential.In this study,a meticulously designed catalyst consisting of cobalt-doped nickel(oxy)hydroxide on molybdenum disulfide heterojunction was developed.The presence of molybdenum in a high valence state promoted the adsorption of tert-butyl hydroperoxide,leading to the formation of critical radical intermediates.In addition,the incorporation of cobalt doping regulated the electronic structure of nickel,resulting in a lower energy barrier.As a result,the heterojunction catalyst demonstrated a selectivity of 85.36% for cleaving the C_(α)-C_(β)bond in lignin model compound,achieving a substrate conversion of 93.69% under ambient conditions.In addition,the electrocatalyst depolymerized 49.82 wt% of soluble fractions from organosolv lignin(OL),resulting in a yield of up to 13 wt% of aromatic monomers.Significantly,the effectiveness of the prepared electrocatalyst was also demonstrated using industrial Kraft lignin(KL).Therefore,this research offers a practical approach for implementing electrocatalytic oxidation in lignin refining.
基金The present work was funded by the Natural Science Foundation of Jilin Provincial Science&Technology Department(Grant No.20180101081JC,20200403034SFthe Science and Technology Project of the Education Department of Jilin Province(Grant No.JJKH20190125KJ).Besides,we would thank to the supervision of Professor Wei Feng from Jilin University for this work.
文摘Cobalt oxyhydroxide(CoOOH)has been turned out to be a high-efficiency catalyst for peroxymonosulfate(PMS)activation.In this study,CoOOH was loaded on bismuth oxide(Bi_(2)O_(3))using a facile chemical precipitation process to improve its catalytic activity and stability.The result showed that the catalytic performance on the 2,4-dichlorophenol(2,4-DCP)degradation was significantly enhanced with only 11 wt%Bi_(2)O_(3)loading.The degradation rate in the CoOOH@Bi_(2)O_(3)/PMS system(0.2011 min−1)was nearly 6.0 times higher than that in the CoOOH/PMS system(0.0337 min−1).Furthermore,CoOOH@Bi_(2)O_(3)displayed better stability with less Co ions leaching(16.4%lower than CoOOH)in the PMS system.These phenomena were attributed to the Bi_(2)O_(3)loading which significantly increased the conductivity and specific surface area of the CoOOH@Bi_(2)O_(3)composite.Faster electron transfer facilitated the redox reaction of Co(III)/Co(II)and thus was more favorable for reactive oxygen species(ROS)generation.Meanwhile,larger specific surface area furnished more active sites for PMS activation.More importantly,there were both non-radical(^(1)O_(2))and radicals(SO_(4)^(−)•,O_(2)^(−)•,and OH•)in the CoOOH@Bi_(2)O_(3)/PMS system and^(1)O_(2)was the dominant one.In general,this study provided a simple and practical strategy to enhance the catalytic activity and stability of cobalt oxyhydroxide in the PMS system.
基金supported by the National Natural Science Foundation of China (22272047, 21905088, and 22102155)China Postdoctoral Science Foundation (2021M692909 and 2022T150587)the Provincial Natural Science Foundation of Hunan (2022JJ10006)。
