Boosting Photocatalytic Oxygen Evolution: Purposely Constructing Direct Z-Scheme Photoanode by Modulating the Interface Electric Field

Ti-Fe₂O₃ photoanode has received widespread attention in photoelectrochemical(PEC) water spilling because of its optimized oxidative and reductive capability of composites catalyst. However, its low efficiency could limit its development. Herein, in order to improve the efficiency of PEC water spilling, the all-solid-state direct Z-scheme Ti-ZnFe₂O₄/Ti-Fe₂O₃(TZFO/Ti-Fe₂O₃) nanorod arrays composited with the ideal energy band structure are synthesized by modulating the Fermi level of TZFO for PEC water splitting. The photophysical methods in this work, including the Kelvin probe measurement and transient photovoltage spectroscopy(TPV) measurement, are applied to explore the migration behavior of electric charges at the enhanced interface electric field. Finally, the Z-scheme charge transfer mechanism of TZFO/Ti-Fe₂O₃ photoanode is proved successfully. Benefiting from the desirable charge transfer at interface electric field, the TZFO/Ti-Fe₂O₃ exhibits the outstanding photocatalytic oxygen evolution reaction(OER) performance, and the photocurrent of 60TZFO/Ti-Fe₂O₃ photoanode reaches 2.16 mA/cm² at 1.23 V vs. reversible hydrogen electrode(RHE), which is three times higher than that of pure Ti-Fe₂O₃ photoanode. This work provides a facile approach of modulating interface electric field to optimize the Z-scheme charge-transfer process.     

Recent Advance of Tellurium for Biomedical Applications

Tellurium(Te) nanomaterials have aroused a wide interest in semiconductor, thermoelectric, piezoelectric, as well as biomedical applications. The last decades of reports indicated a major nanostructure of one-dimensional (1D) Te on account of its inherent structural anisotropy. Two-dimenional(2D) Te has been newly developed and drawn a lot of interests recently. This review presents the intrinsic biological potential of Te-based nanomaterials and summarizes their up-to-date advance in phototherapy and reactive oxygen species(ROS)-related applications in the biomedical field.     

阻抑动力学光度法测定痕量铜

在pH 4.5的HAc-NaAc缓冲溶液中, 痕量铜对KBrO3氧化亮绿SF的褪色反应有明显的阻抑作用, 据此建立了测定痕量铜的新方法. 方法的线性范围为0.004～0.048 μg/mL, 检出限为8.63×10-4 μg/mL, 已用于人发中铜的测定.     

乌骨鸡肌肉中肌肽的鉴定与测定

肌肽是具有抗氧化、抗衰老等多种活性的功能性二肽. 建立了一种高效液相色谱测定鸡肌肉中肌肽的新方法, 该法采用NH2柱分离, 样品无需衍生, 操作简便. 通过该法和HPLC-MS 联用技术鉴定了乌骨鸡肌肉中存在肌肽, 同时比较乌骨鸡和普通白洛克鸡肌肉中肌肽的量. 结果表明: 该法适合于肌肉中肌肽的测定, 测定结果显示, 乌骨鸡肌肉中肌肽量约0.45%, 普通白洛克鸡肌肉中约0.22%. 乌骨鸡肌肉中肌肽量显著高于普通白洛克鸡, 这表明肌肽可能是体现乌骨鸡滋补营养作用的主要成分之一.     

新型固定化pH梯度毛细管等电聚焦方法用于蛋白分离

通过化学键合建立一种固定化pH梯度的方法,用于毛细管等电聚焦分离蛋白质.采用微流控泵驱动毛细管内的聚焦区带,通过调节泵的流量,从而调节聚焦区带的迁移速度.该方法避免了自由溶液聚焦时两性电解质所带来的影响,实现了高灵敏度及检测波长自由选择等优点,适用于两步法毛细管电泳等电聚焦分离蛋白质等两性电解质.本文考察了对牛血清白蛋白和血红蛋白两种蛋白质混合物的分离,证明了该方法可行.     

DNA-HRP/聚M-酪氨酸共修饰电极的制备及其电化学性能的研究

以聚L-酪氨酸膜为载体,固载DNA和辣根过氧化物酶(HRP)制备过氧化氢生物传感器.该传感器对H2O2表现出良好的催化还原特性,具有灵敏度高,稳定性好且易于制作等特点.其线性响应范围为:2.0×10-6～1.1×10-2 mol/L,检出限为8.0×10-7 mol/L (S/N=3).     

青钱柳中多糖的测定

建立了一种测定青钱柳中多糖的方法. 青钱柳样经80%乙醇回流除去单糖、双糖、低聚糖、多酚、氨基酸等杂质后用水提取, 得青钱柳多糖, 其含量采用蒽酮-硫酸法比色测定, 用精制青钱柳多糖测得青钱柳多糖对葡萄糖的换算因子. 采用该方法测定简便可行, 供试液在8 h内显色稳定, 重现性较好, 平均回收率为100.8%, RSD为1.9% (n=3). 所测江西修水青钱柳中多糖含量为4.39%.     

新型碳基渗滤膜在易燃液体残留物提取检验中的应用

用自制的碳基渗滤膜,以自制的红外提取装置测定了该膜对苯的回收率为68%,考察了温度、压力、提取时间等对碳基渗滤膜应用的影响,主要介绍了将该碳基渗滤膜应用于现场易燃液体残留物的提取,通过水泥地面添加易燃液体的提取检验,棉布、化纤布上易燃液体残留物的提取检验测试了碳基渗透膜的提取回收能力.该碳基渗滤膜可以应用于纵火现场易燃液体残留物的提取检验.     

室温离子液体在分离分析中的应用

室温离子液体是指室温或接近室温下全部由离子组成的有机液体物质,具有不挥发,不易燃,溶解范围大,对空气和热稳定等特点,作为一种“可设计”型的环境相对友好溶剂,已被成功应用于分离分析领域中。本文重点综述了离子液体近年来在毛细管电泳、液相色谱及气相色谱中的应用进展,也对离子液体在质谱和光谱中的应用作了介绍。     

尿素酶固载于纳米二氧化钛多孔膜上的尿素生物传感器

在钛丝基体上沉积一层纳米二氧化钛(TiO2)多孔膜,然后直接将尿素酶吸附在TiO2膜上。基于TiO2膜的pH响应,发展了一种廉价的、易于微型化的pH敏尿素酶传感器。采用石英微天平、红外光谱和紫外可见光谱等手段研究尿素酶在TiO2膜上的物理固载行为。由于纳米TiO2在紫外光下光自洁特性可获得高度洁净的表面,石英微天平研究表明在光自洁后的TiO2膜上尿素酶的吸附具有很好的重复性和稳定性,吸附量为0.22mmol/g,吸附平衡常数k为3.15×105L/mol。采用电位法测定了尿素酶/TiO2复合膜电极的性能及其影响因素,在1.0 mmol/L pH 7~8 PBS,35℃,尿素的响应范围为8.5×10-5~1.5×10-1mol/L,相关系数r为0.993 7,检出限为6×10-5mol/L。