Catalytic reduction of 4-nitrophenol(4-NP)pollutant to the high-value 4-aminophenol(4-AP)with a clean hydrogen donor holds significant importance yet great challenges owing to the difficult activation of nitro and H s...Catalytic reduction of 4-nitrophenol(4-NP)pollutant to the high-value 4-aminophenol(4-AP)with a clean hydrogen donor holds significant importance yet great challenges owing to the difficult activation of nitro and H species.In this work,Ag tailoring Frustrated Lewis pairs(FLPs)of CeO_(2)(Ag/CeO_(2))were successfully fabricated for electrochemical reduction reaction of 4-NP(4-NP ERR).As a result,the bond of Ag with O atom changed the state of the Ce-O bond and electron density,where the tailored FLPs were the key factor for enhancing absorption and activation.The reaction rate of Ag/CeO_(2)reached up to 4.70 mmol·min^(-1)(Faraday efficiency:99.5%),which was about four times of CeO_(2).Additionally,this study delved into the proton-coupled electron processes to further understand the mechanism of 4-NP ERR.Therefore,in this study,we have endeavored to investigate the role of tailored FLPs sites and utilize this structure-function relationship to achieve environmentalfriendly chemical synthesis.展开更多
A method was developed for the determination of tetraethyl ammonium （TEA） by reversed-phase ion- pair chromatography with indirect ultraviolet detection, Chromatographic separation was achieved on a reversed-phase C...A method was developed for the determination of tetraethyl ammonium （TEA） by reversed-phase ion- pair chromatography with indirect ultraviolet detection, Chromatographic separation was achieved on a reversed-phase C18 column using background ultraviolet absorbing reagent - ion-pair reagent - organic solvent as mobile phase. The effects of the background ultraviolet absorbing reagents, detection wavelength, ion-pair reagents, organic solvents and column temperature on the determination method were investigated and the retention rules discussed. Results found that TEA could be successfully analyzed by using 0.7 mmol/L 4-aminophenol hydrochloride and 0.15 mmol/L 1-heptanesulfonic acid sodium mixed with 20% （v/v） methanol as mobile phase at a UV detection wavelength of 230 nm. Under these conditions, the retention time of tetraethyl ammonium was 2.85 min. The detection limit （S/N = 3） for TEA was 0.06 mg/L. The relative standard deviations （n = 5） for peak area and retention time were 0.35% and 0.02%, respectively. The method has been successfully applied to the determination of synthesized tetraethyl ammonium bromide. Recovery of tetraethyl ammonium after spiking was 99.1%.展开更多
Nickel oxide nanoparticles decorated carbon nanotube nanocomposites （NiO.CNT NCs） were prepared in a basic medium by using facile wet-chemical routes. The optical, morphological, and structural properties of NiO.CNT...Nickel oxide nanoparticles decorated carbon nanotube nanocomposites （NiO.CNT NCs） were prepared in a basic medium by using facile wet-chemical routes. The optical, morphological, and structural properties of NiO.CNT NCs were characterized using Fourier transformed infra-red （FT-IR）, Ultra-violet visible （UV/Vis） spectroscopy, field-emission scanning electron microscopy （FESEM）, X-ray energy dispersed spectroscopy （XEDS）, X-ray photoelectron spectroscopy （XPS）, and powder X-ray diffraction （XRD） methods. Selective 4-aminophenol （4-AP） chemical sensor was developed by a fiat glassy carbon electrode （GCE, surface area： 0.0316 cm2） fabricated with a thin-layer of NCs. Electrochemical responses including higher sensitivity, large dynamic range （LDR）, limit of detection （LOD）, and long-term stability towards 4-AP were obtained using the fabricated chemical sensors. The calibration curve was found linear （R2 = 0.914） over a wide range of 4-AP concentration （0.1 nmol/L-0.1 tool/L）. In perspective of slope （2 x 10.5 gA/gM）, LOD and sensitivity were calculated as 15.0 ＋ 0.1 pM and -6.33 - 10.4 gA/（gM.cm） respectively. The synthesized NiO.CNT NCs using a wet-chemical method is a significant route for the development of ultrasensitive and selective phenolic sensor based on nano-materials for environmental toxic substances. It is suggested that a pioneer and selective development of 4-AP sensitive sensor using Ni0.CNT NCs by a facile and reliable current us voltage （I-V） method for the major application of toxic agents in biological, green environmental, and health-care fields in near future.展开更多
基金supported by National Natural Science Foundation of China(22075112)Opening Foundation of State Key Laboratory of Rare Earth Resource Utilization(RERU2023010)+1 种基金Opening Foundation of Key Laboratory of Functional Inorganic Material Chemistry(Heilongjiang University)Ministry of Education,China,Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX24_4006).
文摘Catalytic reduction of 4-nitrophenol(4-NP)pollutant to the high-value 4-aminophenol(4-AP)with a clean hydrogen donor holds significant importance yet great challenges owing to the difficult activation of nitro and H species.In this work,Ag tailoring Frustrated Lewis pairs(FLPs)of CeO_(2)(Ag/CeO_(2))were successfully fabricated for electrochemical reduction reaction of 4-NP(4-NP ERR).As a result,the bond of Ag with O atom changed the state of the Ce-O bond and electron density,where the tailored FLPs were the key factor for enhancing absorption and activation.The reaction rate of Ag/CeO_(2)reached up to 4.70 mmol·min^(-1)(Faraday efficiency:99.5%),which was about four times of CeO_(2).Additionally,this study delved into the proton-coupled electron processes to further understand the mechanism of 4-NP ERR.Therefore,in this study,we have endeavored to investigate the role of tailored FLPs sites and utilize this structure-function relationship to achieve environmentalfriendly chemical synthesis.
基金supported by the Natural Science Foundation of Heilongjiang Province(Grant No.B201307)the Ministry of Education of Heilongjiang Province(No.12531192)the Program for Scientific and Technological Innovation Team Construction in Universities of Heilongjiang Province(No. 2011TD010)
文摘A method was developed for the determination of tetraethyl ammonium （TEA） by reversed-phase ion- pair chromatography with indirect ultraviolet detection, Chromatographic separation was achieved on a reversed-phase C18 column using background ultraviolet absorbing reagent - ion-pair reagent - organic solvent as mobile phase. The effects of the background ultraviolet absorbing reagents, detection wavelength, ion-pair reagents, organic solvents and column temperature on the determination method were investigated and the retention rules discussed. Results found that TEA could be successfully analyzed by using 0.7 mmol/L 4-aminophenol hydrochloride and 0.15 mmol/L 1-heptanesulfonic acid sodium mixed with 20% （v/v） methanol as mobile phase at a UV detection wavelength of 230 nm. Under these conditions, the retention time of tetraethyl ammonium was 2.85 min. The detection limit （S/N = 3） for TEA was 0.06 mg/L. The relative standard deviations （n = 5） for peak area and retention time were 0.35% and 0.02%, respectively. The method has been successfully applied to the determination of synthesized tetraethyl ammonium bromide. Recovery of tetraethyl ammonium after spiking was 99.1%.
基金Center of Excellence for Advanced Materials Research(CEAMR),King Abdulaziz University,Jeddah is highly acknowledged for instrumental and technical supports
文摘Nickel oxide nanoparticles decorated carbon nanotube nanocomposites （NiO.CNT NCs） were prepared in a basic medium by using facile wet-chemical routes. The optical, morphological, and structural properties of NiO.CNT NCs were characterized using Fourier transformed infra-red （FT-IR）, Ultra-violet visible （UV/Vis） spectroscopy, field-emission scanning electron microscopy （FESEM）, X-ray energy dispersed spectroscopy （XEDS）, X-ray photoelectron spectroscopy （XPS）, and powder X-ray diffraction （XRD） methods. Selective 4-aminophenol （4-AP） chemical sensor was developed by a fiat glassy carbon electrode （GCE, surface area： 0.0316 cm2） fabricated with a thin-layer of NCs. Electrochemical responses including higher sensitivity, large dynamic range （LDR）, limit of detection （LOD）, and long-term stability towards 4-AP were obtained using the fabricated chemical sensors. The calibration curve was found linear （R2 = 0.914） over a wide range of 4-AP concentration （0.1 nmol/L-0.1 tool/L）. In perspective of slope （2 x 10.5 gA/gM）, LOD and sensitivity were calculated as 15.0 ＋ 0.1 pM and -6.33 - 10.4 gA/（gM.cm） respectively. The synthesized NiO.CNT NCs using a wet-chemical method is a significant route for the development of ultrasensitive and selective phenolic sensor based on nano-materials for environmental toxic substances. It is suggested that a pioneer and selective development of 4-AP sensitive sensor using Ni0.CNT NCs by a facile and reliable current us voltage （I-V） method for the major application of toxic agents in biological, green environmental, and health-care fields in near future.
