应用Fe2+与K3[Fe(CN)6]反应测定还原性物质Vc

在pH 2～3的溶液中,低浓度Fe^2＋与K3[Fe（CN）6]反应产生的蓝色沉淀为近似真溶液,最大吸收波长为710 nm.形成的近似真溶液吸光度随静置时间变化而逐渐变大,30 min后吸光度变化缓慢.K3[Fe（CN）6]过量时,Fe^2＋浓度与吸光度呈很好的线性关系.Fe^2＋浓度较大时,易形成絮状沉淀.在pH 2～3的Fe^3＋-K3[Fe（CN）6]体系中,加入Vc能将Fe^3＋还原成Fe^2＋,进而与K3[Fe（CN）6]反应,30 min后测定蓝色拟真溶液的吸光度,Vc的量与溶液的吸光度同样有很好的线性关系,线性相关系数R〉0.999,检出限为0.94μg.     

碱性电解液中K3[Fe(CN)6]在锌阳极上的自发还原和吸附延长锌镍电池的循环寿命

采用K₃[Fe(CN)₆]作为锌镍电池的电解液添加剂,克服了锌阳极的变形。此外,通过一系列实验设计和表征,探索了电解液中金属锌与K₃[Fe(CN)₆]的反应机理。通过XRD (X-ray diffraction)和XPS (X-ray photo-electron spectroscopy)测试,我们发现金属锌在KOH水溶液中能够与K₃[Fe(CN)₆]反应,将[Fe(CN)₆]^3–还原为[Fe(CN)₆]⁴⁻。添加K₃[Fe(CN)₆]的锌镍电池实现了更长的循环寿命,比不添加K₃[Fe(CN)₆]的锌镍电池长3倍以上。在相同循环次数下,改性电解质中锌阳极循环不仅形状变化较小,而且没有出现“死”锌现象,电极添加剂和粘结剂也没有发生偏析。此外,不同于一般的有机添加剂,K₃[Fe(CN)₆]的加入不仅不会增大电极的极化,还能够提高锌镍电池的放电容量和倍率性能。因此,考虑到这一改性策略有着较高的可行性和较低的成本,K₃[Fe(CN)₆]添加剂在锌镍电池的实际应用中具有极大的推广潜力。     

碱性电解液中K3[Fe(CN)6]在锌阳极上的自发还原和吸附延长锌镍电池的循环寿命

In view of the continuously worsening environmental problems, fossil fuels will not be able to support the development of human life in the future. Hence, it is of great importance to work on the efficient utilization of cleaner energy resources. In this case, cheap, reliable, and eco-friendly grid-scale energy storage systems can play a key role in optimizing our energy usage. When compared with lithium-ion and lead-acid batteries, the excellent safety, environmental benignity, and low toxicity of aqueous Zn-based batteries make them competitive in the context of large-scale energy storage. Among the various Zn-based batteries, due to a high open-circuit voltage and excellent rate performance, Zn-Ni batteries have great potential in practical applications. Nevertheless, the intrinsic obstacles associated with the use of Zn anodes in alkaline electrolytes, such as dendrite, shape change, passivation, and corrosion, limit their commercial application. Hence, we have focused our current efforts on inhibiting the corrosion and dissolution of Zn species. Based on a previous study from our research group, the failure of the Zn-Ni battery was caused by the shape change of the Zn anode, which stemmed from the dissolution of Zn and uneven current distribution on the anode. Therefore, for the current study, we selected K₃[Fe(CN)₆] as an electrolyte additive that would help minimize the corrosion and dissolution of the Zn anode. In the alkaline electrolyte, [Fe(CN)₆]^3– was reduced to [Fe(CN)₆]^4– by the metallic Zn present in the Zn-Ni battery. Owing to its low solubility in the electrolyte, K₄[Fe(CN)₆] adhered to the active Zn anode, thereby inhibiting the aggregation and corrosion of Zn. Ultimately, the shape change of the anode was effectively eliminated, which improved the cycling life of the Zn-Ni battery by more than three times (i.e., from 124 cycles to more than 423 cycles). As for capacity retention, the Zn-Ni battery with the pristine electrolyte only exhibited 40% capacity retention after 85 cycles, while the Zn-Ni battery with the modified electrolyte (i.e., containing K₃[Fe(CN)₆]) showed 72% capacity retention. Moreover, unlike conventional organic additives that increase electrode polarization, the addition of K₃[Fe(CN)₆] not only significantly reduced the charge-transfer resistance in a simplified three-electrode system, but also improved the discharge capacity and rate performance of the Zn-Ni battery. Importantly, considering that this strategy was easy to achieve and minimized additional costs, K₃[Fe(CN)₆], as an electrolyte additive with almost no negative effect, has tremendous potential in commercial Zn-Ni batteries.     

K4[Ru(CN)6]对T-颗粒溴碘化银乳剂感光性能及光电子寿命影响的研究

本文研究了K₄[Ru(CN)₆]掺杂剂对T-颗粒溴碘化银乳剂感光性能以及光电子寿命的影响,研究结果表明,掺杂剂的掺杂量、掺杂位置以及在乳剂颗粒内部的分布区域对乳剂的感光性能都有影响.掺杂位置接近表面或接近颗粒几何核心时效果明显,掺杂位置接近富碘区域时,乳剂的感光度变化不明显或是下降.掺杂位置决定了掺杂剂的最佳用量,在66%—92%位置掺杂时,感光度提高最为显著.与未掺杂乳剂相比,最佳掺杂位置和最佳掺杂量乳剂的自由光电子与浅束缚光电子的寿命都有所延长.     

掠射椭偏术对K_4〔Fe(CN)_6〕/K_3〔Fe(CN)_6〕电极反应的研究

提出掠射椭圆偏振测试技术的实验方案,应用该掠射式技术结合循环伏安法研究了在镀有Ｉｎ２Ｏ３玻璃片上进行的Ｋ４〔Ｆｅ（ＣＮ）６〕／Ｋ３〔Ｆｅ（ＣＮ）６〕电极反应．结果证明：掠射椭圆偏振术可在电化学反应过程中现场测定椭圆偏振参数及其变化规律,这些规律与所发生的表面电化学反应规律相对应,由此可以对电极体系进行研究;现场掠射椭圆偏振术还能用于分析表面扩散层的性质,弥补其它界面研究方法的缺陷．     

电化学石英晶体阻抗系统研究金电极上Fe(CN)_6~(3-)/Fe(CN)_6~(4-)电化学过程

电化学过程的石英晶体阻抗分析法已用于现场获取电活性聚合物粘弹性等信息［１,２］．本文联用ＨＰ４３９５Ａ阻抗／网络／频谱分析仪和ＥＧ＆ＧＭ２８３恒电位仪开发出电化学石英晶体阻抗系统（ＥｌｅｃｔｒｏｃｈｅｍｉｃａｌＱｕａｒｔｚＣｒｙｓｔａｌＩｍｐｅｄａｎ...     

Co_(3)O_(4)/CeO_(2)复合电极材料的制备与超级电容器电化学性能研究

利用六水合硝酸铈、六水合硝酸钴和尿素通过水热法合成麦叶状Co_(3)O_(4)/CeO_(2)复合电极材料,对其进行电化学性能分析,发现Co_(3)O_(4)/CeO_(2)复合电极材料具有良好的电化学可逆性和功率特性,且其电容特性和大电流放电特性也很优越,是理想的超级电容器材料.     

掺Fe3+MnO2超级电容器电极材料的制备

化学掺杂;掺Fe3+MnO2超级电容器电极材料的制备     

基于铁氰化钾电子媒介体及醛基吡啶盐的电化学免疫传感器

采用聚二烯丙基二甲基氯化铵(PDDA)将铁氰化钾电子媒介体固定在电极表面,构建免标记的电化学免疫传感器. 醛基吡啶盐不仅作为基底物质直接固定抗体,还可以很好地增强电极表面的导电性能. 将构建的传感器用于肿瘤标志物甲胎蛋白的检测. 其线性范围为0.01-20 ng·mL^-1,检测下限为0.004 ng·mL^-1（3 S/N）. 此传感器的构建简单方便、无标记、特异性好,为甲胎蛋白及其他肿瘤标志物提供了新的检测方法.     

基于铁氰化镍的非标记型核酸适配体电化学传感器检测凝血酶

在玻碳电极（GCE）表面首先用增敏作用的多壁碳纳米管(MWCNTs)夹心于两层电沉积的铁氰化镍（NiHCF）氧化还原电化学探针之间,然后以金纳米粒子为固定核酸适配体的载体,构建了检测凝血酶的非标记型核酸适配体生物传感器。 利用扫描电子显微镜(SEM)对MWCNTs和NiHCF的形貌进行了表征。 利用电化学阻抗谱对传感器的组装过程进行了监测,用循环伏安法（CV）和差分脉冲伏安法（DPV）对传感器的电化学行为进行了研究。 以铁氰化镍为探针的传感器对凝血酶的检测在1.0 ng/L~1.0 mg/L范围内呈良好的线性关系,相关系数为0.998,检测限为0.2 ng/L(S/N=3)。     

铁氰酸镍膜修饰金电极的研制及应用

通过层层组装的方法,将Ni^2＋和[Fe（CN）6]^3-交替沉积在巯基乙酸功能化的金电极表面．首次成功制备了铁氰酸镍多层膜修饰电极,用循环伏安法研究了该多层膜的电化学行为,实验表明峰电流随膜层数的增加而增加,膜均匀增长．该修饰电极对一价金属离子Na^＋,K^＋,NH4^＋具有选择性响应,尤其对K^＋存在准能斯特响应,响应范围0．01～1．0mol／L;而且该电极对抗坏血酸（AA）和S2O3^2-体系的氧化具有良好的电催化作用,线性范围分别为：1．14×10^-4～1．14×10^-3mol／L和5．0×10^-4～3．1×10^-3mol／L．     

基于碳纳米管和铁氰酸镍纳米颗粒协同作用的葡萄糖生物传感器

将制备的铁氰酸镍纳米颗粒(NiNP)与多壁碳纳米管(CNT)混合, 分散于壳聚糖溶液中, 形成一种新的纳米复合成分(NiNP-CNT-CHIT), 将其修饰在玻碳电极表面. 新复合膜体现了NiNP和CNT之间的协同作用, 由于CNT的良好的传递电子性能, 促使NiNP催化氧化还原能力有了较大的提高. 此NiNP-CNT-CHIT复合膜修饰的玻碳电极在较低电位下对过氧化氢具有良好的电催化性能, 与NiNP-CHIT膜比较, 测定H₂O₂的灵敏度增大了50倍. 通过戊二醛在电极表面固定葡萄糖氧化酶制备了一种新的葡萄糖传感器. 该传感器在－0.2 V下对葡萄糖的线性范围为0.05～10 mmol/L, 检测下限为10 μmol/L.     

Amperometric Determination of Inositol Based on Electrocatalytic Oxidation on a Glass Carbon Electrode Modified by Nickel Hexacyanoferrate Films

Abstract

A novel method to determinate inositol based on the electrocatalytic oxidation of inositol on the surface of a nickel hexacyanoferrate (NiHCF)–modified electrode was reported. The determination of inositol can be performed in the range of 1.0×10^?4 to 5.8×10^?3 mol/L with a detection limit of 5.0×10^?5 mol/L.     

纳米铁氰化镍修饰铝电极对抗坏血酸的电催化氧化

利用多孔阳极氧化铝作模板,用化学修饰方法在铝基体上制备了纳米铁氰化镍修饰电极。研究了修饰电极的电化学特征及其电催化氧化抗坏血酸的行为。结果表明,纳米铁氰化镍修饰铝电极的循环伏安图上呈现一对可逆氧化还原峰。检测抗坏血酸,纳米铁氰化镍修饰铝电极比铁氰化镍修饰铝电极有更高的灵敏度。用安培法测定抗坏血酸,线性范围为1×10-6～1.5×10-2mol/L,检出限为2.4×10-7mol/L。本方法应用于实际样品中抗坏血酸的检测,结果令人满意。     

Superior Supercapacitor Properties of Composite Powders with Amorphous NiO Nanoclusters Distributed Uniformly in an Amorphous Carbon Matrix

Amorphous nickel oxide–carbon composite powders have been prepared using a facile spray‐drying process. The nickel nitrate–citrate hydrate precursor powders were transformed into an amorphous NiO–carbon composite powder through a post‐treatment at 250 °C for 1 h. The excellent supercapacitor performance of the amorphous NiO–carbon composite powder can be ascribed to the unique electrochemical behavior of the ultrafine amorphous NiO nanoclusters.     

立方亚铁氰化锌钾颗粒的制备和抗菌性能研究

研究了以硝酸锌和亚铁氰化钾为原料制备立方状亚铁氰化锌钾抗菌材料的方法。通过比较不同产物的形貌、产率、化学组成、晶型和抗菌性能,确定了最佳的反应物配比。采用SEM、XRD、ICP等方法表征了样品的颗粒形貌、晶型和元素组成等信息;并检测了添加了立方状亚铁氰化锌钾颗粒的涂层的抗菌性能。研究发现当锌离子和亚铁氰化钾的物质的量比在1.5/1时,所得样品白度好、形貌稳定且对金色葡萄球和大肠杆菌都表现出了良好的抗菌性能。     

Facile In Situ Synthesis of Hierarchical Porous Ni/Ni(OH)2 Hybrid Sponges with Excellent Electrochemical Energy‐Storage Performances for Supercapacitors

Herein, we report the in situ growth of single‐crystalline Ni(OH)₂ nanoflakes on a Ni support by using facile hydrothermal processes. The as‐prepared Ni/Ni(OH)₂ sponges were well‐characterized by using X‐ray diffraction (XRD), SEM, TEM, and X‐ray photoelectron spectroscopy (XPS) techniques. The results revealed that the nickel‐skeleton‐supported Ni(OH)₂ rope‐like aggregates were composed of numerous intercrossed single‐crystal Ni(OH)₂ flake‐like units. The Ni/Ni(OH)₂ hybrid sponges served as electrodes and displayed ultrahigh specific capacitance (SC=3247 F g^?1) and excellent rate‐capability performance, likely owing to fast electron and ion transport, sufficient Faradic redox reaction, and robust structural integrity of the Ni/Ni(OH)₂ hybrid electrode. These results support the promising application of Ni(OH)₂ nanoflakes as advanced pseudocapacitor materials.