CoSe-凹土对电极设计构筑及其电催化性能研究

为了提高染料敏化太阳能电池的光伏性能,以凹土为载体,采用溶剂热法合成CoSe-凹土纳米复合材料,利用喷涂法制备CoSe-凹土薄膜,从而设计构筑出电催化性能优异的CoSe-凹土对电极。由物相与结构形貌表征分析可知,凹土在CoSe纳米材料中分布比较均匀,有利于提高对电极的电催化性能。电化学测试结果表明,当CoSe与凹土质量比约为4∶1时,CoSe-凹土对电极表现出了比铂电极更加优异的电催化性能。同时,染料敏化太阳能电池也展现出了较好的光伏性能,其光电转换效率有效提高到6.05%,高于以铂电极为对电极的器件效率(5.78%)。     

钛丝负载Pt/TiO2电极的制备及其电催化测定化学需氧量研究

采用阳极氧化的方法,在钛丝上制备TiO2纳米管阵列薄膜,用恒电流沉积的方法在TiO2纳米管表面沉积Pt纳米晶,制备了钛丝负载的Pt/TiO2电极.用SEM对电极的形貌进行了表征,纳米管长度在3.5～10 μm之间与氧化电压和氧化时间密切相关,Pt纳米晶均匀沉积在TiO2纳米管表面.用极化曲线、循环伏安曲线、电流-时间曲线对Pt/TiO2电极的电催化性能进行表征.当沉积电流密度大于1.0 mA/cm2时,制备的Pt/TiO2电极的电催化性能显著高于Pt电极.而且,在甲醛等五种有机物溶液中的电催化结果表明,净电流和理论COD之间表现出很好的线性相关性,说明钛丝负载的Pt/TiO2电极可用于电催化快速检测水体中的化学需氧量.     

Ionic liquid-assisted hydrothermal synthesis of TiO2 nanoparticles and its applications towards the photocatalytic activity and electrochemical sensor

This work reports the synthesis of TiO₂ nanoparticles via ionic liquid-assisted hydrothermal method at 130?°C for two days. The obtained product was characterised by various techniques. The X-ray diffraction data reveal the anatase phase TiO₂ nanoparticles with crystallite size 37 nm. The Fourier transform infrared spectrum shows a band at 400 cm^?1 due to Ti–O–Ti stretching vibration, in addition to the presence of ionic liquid. The UV–Vis spectrum of TiO₂ nanoparticles shows an absorption band at 314 nm which indicates a blueshift compared with that of bulk TiO_2. The transmission electron microscopy images show almost spherical-shaped nanoparticles with an average diameter of 40–80 nm. TiO₂ nanoparticles exhibit excellent photocatalytic activity for the degradation of trypan blue, and also help in the reduction of Cr⁺⁶ to Cr⁺³. TiO₂ nanoparticles modified glassy carbon electrode exhibits better electrocatalytic oxidation towards dopamine compared with bare glassy carbon electrode.     

Enhanced degradation of organic wastewater containing p-nitrophenol by a novel wet electrocatalytic oxidation process: Parameter optimization and degradation mechanism

This paper explored a novel advanced oxidation process (AOP) for wastewater treatment—wet electrocatalytic oxidation (WEO), which introduced a small current into wet air oxidation (WAO) to promote the formation of hydroxyl radical and accelerate the oxidation of organic pollutants. The results showed that this novel process could couple the advantages of both WAO and electrochemical oxidation (EO). The effects of major operational factors of WEO were studied at relatively moderate condition (T = 100–160 °C, C = 1000 mg L⁻¹, P_O2 = 4 TOD, P_N2 = 0.50 MPa, current density = 0–7.08 mA cm⁻² and pH 2.7–10.6) aiming to p-nitrophenol (PNP) degradation, TOC and COD removal. The cost-effective operational parameters were found and the current efficiencies were highly beyond 100% with the maximum value of 386%. The degradation mechanism of WEO was carefully studied based on the formation of free radical. After the detail analysis of Hammett theory and quantitative structure-activity relationships (QSAR), the reaction pathway of hydroxyl radical with PNP was analyzed with the help of Gaussian 03W and the probable degradation pathway of PNP by WEO was deduced.     

PTFE-F-PbO2 电极在H2SO4溶液中的析氧行为

F-PbO2 electrode and polytetrafluoroethylene （PTFE） doped F-PbO2 electrode （PTFE-F-PbO2） were prepared on a plexiglas sheet substrate by a series of procedure including chemical and electrochemical depositions. The electrochemical activities of these two electrodes for oxygen evolution （OE） reaction were examined by electrochemical tests. In comparison with F-PbO2, PTFE-F-PbO2 electrode exhibited larger active surface area and higher oxygen vacancy deficiency, which resulted in its higher electrocatalytic activity for OE. In addition, both exchange current density and activation energy of the electrodes for OE were calculated in terms of active surface area. The values of exchange current density and activation energy in 0.5 mol·L^-1 H2SO4 aqueous solution were 1.125×10^ -3 mA·cm^-2 and 18.62 kJ·mol^-1 for PTFE-F-PbO2, and 8.384×10^-4 mA·cm^- 2 and 28.98 kJ·mol^-1 for F-PbO2, respectively. Because these values are calculated on the basis of the active surface areas of the electrodes, the enhanced activity of PTFE-F-PbO2 can be attributed to an increase in oxygen vacancy deficiency of PbO2 due to doping by PTFE. The influence of PTFE adulteration on the activity of PbO2 film electrode for OE was investigated in detail in this study.     

亚硝酸根在含钴介孔分子筛修饰电极上的电催化氧化行为研究

本文基于新型的含钴介孔分子筛（CoMCM-41）对亚硝酸根离子氧化反应的催化作用,研制了CoMCM-41-PVA膜化学修饰电极的电化学传感器制备,以及在pH=7．0的磷酸盐缓冲溶液中,0．72V的工作电位下,对NO2^-的检测。亚硝酸根离子浓度在2．0×10^-7～1．1×10^-5 mol／L范围内与电流成线性关系,相关系数r=0．9994,检测下限为5．0×10^-8mol／L。     

酸性氯化铜蚀刻废液电解再生用阳极的筛选

采用热分解法制备了8种DSA涂层阳极,通过循环伏安曲线、极化曲线、强化寿命等测试研究了不同涂层的电催化性能。结果表明,RuIrTiSnMn/Ti涂层阳极在酸性蚀刻废液电解再生工艺的阳极电流密度范围内具有最高的析氯电位,且强化寿命高(为538h),涂层成本最低,可作为酸性蚀刻废液电解再生工艺用的阳极。     

电镀废水有机污染物的电催化氧化中试研究

采用新型钛基网状电极对电镀废水进行了电催化氧化研究,在间歇试验条件下考察了电流密度、处理时间和原水初始pH对有机污染物处理效果的影响,在连续试验条件下考察了工艺的稳定性,并结合GC-MS中间产物分析探讨了电催化氧化对废水可生化性的影响。结果表明,处理时间、电流密度和原水起始pH对COD去除效果有显著影响,优化的试验参数为:电流密度100 A.m-2,处理时间3 h,起始pH为中性。在该条件下,废水COD可由439 mg.L-1降至70 mg.L-1,且装置运行稳定,吨水处理能耗为5.7 kWh。长链烷烃等大分子有机物在电催化氧化过程中被分解为短链烷烃和小分子有机物,废水可生化性得到显著改善。     

载铂二氧化钛纳米管电极的制备及电催化性能

用水热法在二氧化钛纳米管上负载纳米铂微粒,制备出大比表面积、高表面原子数的载铂二氧化钛纳米管电极。 SEM和XRD分析证明纳米管上已负载20~30 nm的铂微粒。循环伏安测试结果表明：不含染料的体系中,载铂二氧化钛纳米管电极在0.13 V处的氧化峰电流密度为Pt片电极的10倍;含染料的体系中,载铂二氧化钛纳米管电极上对酸性大红GR的氧化峰电流密度达到Pt片电极上的4.2倍。对酸性大红GR的降解实验表明,载铂二氧化钛纳米管电极催化活性高、降解快速高效     

熔盐法制备自支撑Ni掺杂Mo2C@CFP复合电极及其电催化析氢性能的研究

Mo₂C具有类似于Pt等贵金属的电子结构和催化特性,有望替代Pt等贵金属成为新型非贵金属析氢催化剂,但是纯Mo₂C导电性差且氢释放动力学慢。为提高Mo₂C的电催化析氢性能,本工作采用低温熔盐法在碳纤维纸(CFP)基底上制备了自支撑Mo₂C电催化剂,研究了Mo和MoO₃钼源、Ni和Ni(NO₃)₂镍源掺杂剂、添加炭黑等因素对合成产物物相、显微形貌和结构、电催化性能的影响。结果表明,炭黑和Ni的引入可以促使Mo₂C晶粒细化以及在表面生成褶皱状结构,能够提供更多活性位点,Ni(NO₃)₂的加入能够使采用MoO₃为钼源合成的Mo₂C的晶粒变成纳米花状结构,大大提高了其比表面积,也促进了反应生成的复合电极Ni(NO₃)₂-Mo₂C_CBO@CFP中的电子转移效率,表现出最佳的HER活性,其η₁₀为117 mV,塔菲尔斜率低至73.8 mV dec^_-1。