This work describes the electrochemical behavior of azodicarboxamide(ACA) film immobilized on the surface of penicillamine(PNA)/Zn Se-quantum dot(Zn Se-QD) gold nanoparticle(Au NPs) Au electrode. Electrocatalytic acti...This work describes the electrochemical behavior of azodicarboxamide(ACA) film immobilized on the surface of penicillamine(PNA)/Zn Se-quantum dot(Zn Se-QD) gold nanoparticle(Au NPs) Au electrode. Electrocatalytic activity of modified electrode toward the oxidation of cysteine(Cy SH) was investigated. The surface structure and composition of the sensor were characterized by scanning electron microscopy(SEM). Oxidation of Cy SH on the surface of modified electrode was investigated with cyclic voltammetry, electrochemical impedance spectroscopy(EIS),hydrodynamic voltammetry and chronoamperometry methods. The results show that the PNA/Zn Se-QD/ACA film displays excellent electrochemical catalytic activities towards Cy SH oxidation. The modified electrode shows reproducible behavior and high level of stability during the electrochemical experiments. Also it has short response time, low detection limit, high sensitivity and low operation potential, which can be used as an amperometric sensor for monitoring of Cy SH. The proposed modified electrode was successfully used for determination of Cy SH in real sample such as human serum.展开更多
Selective upgrading of C=O bonds to afford carboxylic acid is significant for the petrochemical industry and biomass utilization.Here we declared the efficient electrooxidation of biomass-derived aldehydes family over...Selective upgrading of C=O bonds to afford carboxylic acid is significant for the petrochemical industry and biomass utilization.Here we declared the efficient electrooxidation of biomass-derived aldehydes family over NiV-layered double hydroxides(LDHs) thin films.Mechanistic studies confirmed the hydroxyl active intermediate(-OH*) generated on the surface of NiV-LDHs films by employing electrochemical impedance spectroscopy and the electron paramagnetic resonance spectroscopy.By using advanced techniques,e.g.,extended X-ray absorption fine structure and high-angle annular dark-field scanning transmission electron microscopy,NiV-LDHs films with 2.6 nm could expose larger specific surface area.Taking benzaldehyde as a model,high current density of 200 mA cm^(-2)at 1.8 V vs.RHE,81.1% conversion,77.6% yield of benzoic acid and 90.8% Faradaic efficiency were reached,which was superior to most of previous studies.Theoretical DFT analysis was well matched with experimental findings and documented that NiV-LDHs had high adsorption capacity for the aldehydes to suppress the side reaction,and the aldehydes were oxidized by the electrophilic hydroxyl radicals formed on NiV-LDHs.Our findings offer a universal strategy for the robust upgrading of diverse biomass-derived platform chemicals.展开更多
Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and ...Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and high rate-determining step energy barrier for difficult to dehydrogenate.Herein,we report Mn_(x)Ce_(1-x)O_(2)/CNT catalyst for accelerated reaction kinetics.Theoretical and experimental studies indicate that Ce sites promote TL adsorption and polyvalent Mn modulates the electronic structure of Ce sites reducing the rate-determining step energy barrier.This results in increasing^(*)C_(6)H_(5)CH_(2)coverage and effectively accelerating TL oxidation reaction(TOR)kinetics.Excitingly,the Faraday efficiency(FE)and BAC yield of optimized Mn_(0.6)Ce_(0.4)O_(2)/CNT at 2.6 V vs.RHE could reach 85.9%and 653.9 mg h^(-1)cm^(-2),respectively.In addition,the Mn_(0.6)Ce_(0.4)O_(2)/CNT displays a high selectivity of 96.3%for BAC.Combining the TL oxidation reaction with hydrogen evolution reaction,the anion exchange membrane electrolyzer of Mn_(0.6)Ce_(0.4)O_(2)/CNT(+)||Pt/C(-)can reach 100 mA cm^(-2)at the voltage of 3.0 V,in which the BAC yield is 579.4 mg h^(-1)cm^(-2)and the FE is 83.6%.This work achieved high selectivity of TOR at industrial-relevant current densities of 100 mA cm^(-2)at the low voltage for the first time.展开更多
基金the support of this work by the Khorramabad Branch, Islamic Azad University for financial support
文摘This work describes the electrochemical behavior of azodicarboxamide(ACA) film immobilized on the surface of penicillamine(PNA)/Zn Se-quantum dot(Zn Se-QD) gold nanoparticle(Au NPs) Au electrode. Electrocatalytic activity of modified electrode toward the oxidation of cysteine(Cy SH) was investigated. The surface structure and composition of the sensor were characterized by scanning electron microscopy(SEM). Oxidation of Cy SH on the surface of modified electrode was investigated with cyclic voltammetry, electrochemical impedance spectroscopy(EIS),hydrodynamic voltammetry and chronoamperometry methods. The results show that the PNA/Zn Se-QD/ACA film displays excellent electrochemical catalytic activities towards Cy SH oxidation. The modified electrode shows reproducible behavior and high level of stability during the electrochemical experiments. Also it has short response time, low detection limit, high sensitivity and low operation potential, which can be used as an amperometric sensor for monitoring of Cy SH. The proposed modified electrode was successfully used for determination of Cy SH in real sample such as human serum.
基金supported by the National Natural Science Foundation of China(22078374,21776324)the Scientific and Technological Planning Project of Guangzhou(202206010145)+2 种基金the National Ten Thousand Talent Plan,Key-Area Research and Development Program of Guangdong Province(2019B110209003)the Guangdong Basic and Applied Basic Research Foundation(2019B1515120058,2020A1515011149)the Start-up Fund for Senior Talents in Jiangsu University(21JDG060)。
文摘Selective upgrading of C=O bonds to afford carboxylic acid is significant for the petrochemical industry and biomass utilization.Here we declared the efficient electrooxidation of biomass-derived aldehydes family over NiV-layered double hydroxides(LDHs) thin films.Mechanistic studies confirmed the hydroxyl active intermediate(-OH*) generated on the surface of NiV-LDHs films by employing electrochemical impedance spectroscopy and the electron paramagnetic resonance spectroscopy.By using advanced techniques,e.g.,extended X-ray absorption fine structure and high-angle annular dark-field scanning transmission electron microscopy,NiV-LDHs films with 2.6 nm could expose larger specific surface area.Taking benzaldehyde as a model,high current density of 200 mA cm^(-2)at 1.8 V vs.RHE,81.1% conversion,77.6% yield of benzoic acid and 90.8% Faradaic efficiency were reached,which was superior to most of previous studies.Theoretical DFT analysis was well matched with experimental findings and documented that NiV-LDHs had high adsorption capacity for the aldehydes to suppress the side reaction,and the aldehydes were oxidized by the electrophilic hydroxyl radicals formed on NiV-LDHs.Our findings offer a universal strategy for the robust upgrading of diverse biomass-derived platform chemicals.
基金supported by the National Natural Science Foundation of China(52272222)the Taishan Scholar Young Talent Program(tsqn201909114,tsqn201909123)the University Youth Innovation Team of Shandong Province(202201010318)。
文摘Electrocatalytic toluene(TL)oxidation to produce benzoic acid(BAC)process is largely hindered due to sluggish kinetics associated with the transformation of the rate-determining step,because of weak TL adsorption and high rate-determining step energy barrier for difficult to dehydrogenate.Herein,we report Mn_(x)Ce_(1-x)O_(2)/CNT catalyst for accelerated reaction kinetics.Theoretical and experimental studies indicate that Ce sites promote TL adsorption and polyvalent Mn modulates the electronic structure of Ce sites reducing the rate-determining step energy barrier.This results in increasing^(*)C_(6)H_(5)CH_(2)coverage and effectively accelerating TL oxidation reaction(TOR)kinetics.Excitingly,the Faraday efficiency(FE)and BAC yield of optimized Mn_(0.6)Ce_(0.4)O_(2)/CNT at 2.6 V vs.RHE could reach 85.9%and 653.9 mg h^(-1)cm^(-2),respectively.In addition,the Mn_(0.6)Ce_(0.4)O_(2)/CNT displays a high selectivity of 96.3%for BAC.Combining the TL oxidation reaction with hydrogen evolution reaction,the anion exchange membrane electrolyzer of Mn_(0.6)Ce_(0.4)O_(2)/CNT(+)||Pt/C(-)can reach 100 mA cm^(-2)at the voltage of 3.0 V,in which the BAC yield is 579.4 mg h^(-1)cm^(-2)and the FE is 83.6%.This work achieved high selectivity of TOR at industrial-relevant current densities of 100 mA cm^(-2)at the low voltage for the first time.
