The current work focuses on the development of a sensitive and selective electrochemical device based on a graphite screen printed electrode modified with Dy2（WO4）3 nanoparticles（DWO/SPE） for the analysis of epine...The current work focuses on the development of a sensitive and selective electrochemical device based on a graphite screen printed electrode modified with Dy2（WO4）3 nanoparticles（DWO/SPE） for the analysis of epinephrine in samples also containing acetylcholine. The study proves that the sensor has excellent electron-mediating behavior in the oxidation of epinephrine in a 0.1 mol/L phosphate buffer solution（PBS）（pH 7.0）. The application of the DWO/SPE in differential pulse voltammetry（DPV） is found to lead to distinct response for the oxidation of epinephrine and acetylcholine, with the potentials of the epinephrine and acetylcholine peaks（△Ep） to be 550 mV apart. The detection limits of the method for epinephrine and acetylcholine are 0.5 and 0.7 μmol/L（S/N = 3） and the responses are found to be linear in the concentration ranges of 1.0-900.0 μmol/L and 1.0-1200.0 μmol/L in a PBS buffer（pH = 7.0）respectively. The modified electrode was used for the detection of epinephrine and acetylcholine in real samples and found to produce satisfactory results. These results can be a proof that Dy2（WO4）3 nanoparticles can find promising applications in electrochemical sensors to be used for the analysis of（bio）chemical species.展开更多
Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of t...Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.展开更多
文摘The current work focuses on the development of a sensitive and selective electrochemical device based on a graphite screen printed electrode modified with Dy2（WO4）3 nanoparticles（DWO/SPE） for the analysis of epinephrine in samples also containing acetylcholine. The study proves that the sensor has excellent electron-mediating behavior in the oxidation of epinephrine in a 0.1 mol/L phosphate buffer solution（PBS）（pH 7.0）. The application of the DWO/SPE in differential pulse voltammetry（DPV） is found to lead to distinct response for the oxidation of epinephrine and acetylcholine, with the potentials of the epinephrine and acetylcholine peaks（△Ep） to be 550 mV apart. The detection limits of the method for epinephrine and acetylcholine are 0.5 and 0.7 μmol/L（S/N = 3） and the responses are found to be linear in the concentration ranges of 1.0-900.0 μmol/L and 1.0-1200.0 μmol/L in a PBS buffer（pH = 7.0）respectively. The modified electrode was used for the detection of epinephrine and acetylcholine in real samples and found to produce satisfactory results. These results can be a proof that Dy2（WO4）3 nanoparticles can find promising applications in electrochemical sensors to be used for the analysis of（bio）chemical species.
基金supported by National Research Foundation Investigatorship(No.NRF-NRFI201605)。
文摘Though flexible electrochromic devices have shown huge potential application in the fields of safety warning,display and smart windows,limited attention was paid on preparing flexible electrochromic fiber because of the difficulty in fabricating the multilayer electrochromic device structure in one-dimensional form.In this study,a flexible electrochromic nylon fiber based on Ag nanowires(NWs)/PEDOT:PSS/WO3 nanoparticles(NPs)(PEDOT:PSS=poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid)is successfully fabricated,delivering rapid color switching(2.5 and 9 s for bleaching and coloration)and high optical modulation(65.5%at 633 nm),and sustainable to repeated mechanical deformations.Ag NWs,PEDOT:PSS and WO3 NPs were dip-coated on the nylon fiber,resulting in an electrochromic fiber electrode with stable fiber resistance of 50-100Ω/10 cm,which can withstand mechanical deformation against 300 times of bending cycles with bending radius of 0.5 cm,and sustain 30 times of tape-peeling.During the galvanostatic tests,the capacitance of the electrochromic electrode can maintain 70%of the initial value even after 5,000 times of charge-discharge cycles.Even in knotted shape,the fiber still shows excellent color contrast.This study provides a novel method to construct flexible electrochromic fiber and pave the way for the development of flexible optoelectronic devices,such as flexible and wearable displays.
