电吸附电极研究进展

电吸附电极是电吸附处理水装置最重要的组成部分,也是电吸附研究的热点。结合国内外专利技术,重点分析了多孔炭材料电吸附电极。活性炭、活性炭纤维价格低廉易获得,在产业上应用较多,是今后活性炭电极的主要研究趋势;石墨烯和碳纳米材料基体电极具有良好的循环使用性能和高吸附容量,是今后电吸附电极研究的主要方向。     

电吸附水处理技术研究进展

详述了近年来电吸附电极材料的最新研究进展,包括双电层机理研究、传统碳素材料、碳纳米材料、金属氧化物修饰电极以及导电聚合物复合材料电极材料的制备、改性、吸附性能及吸附效果影响因素等。展望了电吸附技术未来的研究热点,认为分级多孔新型纳米材料电极在电吸附技术上具有很大的优势。     

电吸附电极材料的研究进展

电吸附除盐技术是一种正在发展的新型的除盐技术,其中电极材料是制约电吸附性能的关键,也是电吸附技术研究的热点。介绍了电吸附技术原理和4类碳基电极材料的研究进展,对比分析了4类电极材料的优缺点,指出单一电极材料的吸附容量小,不能满足其工业要求,在低成本的条件下对电极材料进行改性处理是今后电吸附电极材料的主要研究方向。     

松针基生物质碳气凝胶-氧化石墨烯复合电极的制备及其对铷、铯电吸附行为

盐湖卤水中的铷、铯是我国具有国际优势的战略资源。它们的分离提取一直是相关研究的难点。电吸附作为一种绿色环保的分离技术受到越来越多的关注,将其应用于铷、铯的富集分离具有较高的研究价值。以松针为原料,使用水热-冷冻干燥-高温碳化法制备了生物质碳气凝胶,以其为主要电极材料,通过添加氧化石墨烯制备了碳气凝胶-氧化石墨烯(PNCA-GO)复合电极,其对Rb⁺、Cs+、Cs⁺显示出了良好的吸附效果,吸附量分别达到0.197 mmol/g和0.209 mmol/g。这为以后廉价碳材料电极的制备及Rb+显示出了良好的吸附效果,吸附量分别达到0.197 mmol/g和0.209 mmol/g。这为以后廉价碳材料电极的制备及Rb⁺、Cs+、Cs⁺的电吸附行为研究提供了一定的参考。     

松针基生物质碳气凝胶-氧化石墨烯复合电极的制备及其对铷、铯电吸附行为

盐湖卤水中的铷、铯是我国具有国际优势的战略资源。它们的分离提取一直是相关研究的难点。电吸附作为一种绿色环保的分离技术受到越来越多的关注,将其应用于铷、铯的富集分离具有较高的研究价值。以松针为原料,使用水热-冷冻干燥-高温碳化法制备了生物质碳气凝胶,以其为主要电极材料,通过添加氧化石墨烯制备了碳气凝胶-氧化石墨烯(PNCA-GO)复合电极,其对Rb~+、Cs~+显示出了良好的吸附效果,吸附量分别达到0.197 mmol/g和0.209 mmol/g。这为以后廉价碳材料电极的制备及Rb~+、Cs~+的电吸附行为研究提供了一定的参考。     

电吸附技术及吸附电极材料研究进展

电吸附技术得益于环保、清洁、简单和节能的技术优势,在海水脱盐淡化及污染物吸附处理领域具有重要的应用潜力。如何构建高电荷容量的吸附电极是构建高效电吸附装置、提高吸附效率的关键所在。本文从电吸附技术原理出发,介绍了电吸附技术吸附储存离子的双电层理论模型,并对电吸附技术的研究进展进行了总结。随后从吸附电极材料制备角度对碳吸附电极、层状金属氧化物吸附电极、复合型吸附电极分别进行综述,对每一类电极材料特点及不足进行了总结,归纳分析了针对各类材料不足之处的解决方案,并基于高效电吸附技术实际应用目标,对吸附电极材料的设计制备进行了展望。     

纳米材料及其三维结构修饰电极检测多巴胺的研究进展

纳米材料构建的化学修饰电极用于多巴胺电化学检测已经被广泛研究。当前电极研究策略主要为采用复合材料并构建三维结构以增大吸附表面积。本综述总结了目前常用的纳米碳修饰材料与纳米金属修饰材料,比较分析了其表面结构形貌对多巴胺吸附的影响及吸附机制,总结了目前常用的构建三维修饰电极的方法。分析结果表明,相对于一维形貌,三维形貌结构的修饰电极往往具有更好的检测能力,三维结构不仅能显著增大表面积,提供更多的吸附位点,还可能产生“薄膜效应”,该效应在一定程度上能提高响应灵敏度,但超过一定限度会减缓响应时间,第一性原理分析表明,多巴胺在纳米修饰电极材料表面的吸附机制是化学吸附。最后指出了在改进修饰电极结构设计合理性、增强抗干扰性和提高选择性,以及新的检测控制机制分析方面需要进一步研究。     

碳载Sb-Pb-Pt电催化纳米材料的制备与结构表征

:通过电化学方法在玻碳表面沉积催化物质研制Sb Pb Pt合金纳米材料。运用循环伏安(CV)、石英晶体微天平 (EQCM)、扫描隧道显微镜 (STM)和X 光电子能谱 (XPS)等技术对其进行表征。结果指出 ,碳载Sb Pb Pt电催化纳米材料的稳定性明显高于电有机合成中常用的Pb和Sb等电极。在酸性介质中碳载Sb Pb Pt电催化纳米材料电极上氢的析出电位负移至 - 0 45V ,有较高的电还原应用价值。通过EQCM技术对纳米薄膜合金电极的形成过程进行原位跟踪和STM观察 ,表明所研制的Sb Pb Pt纳米材料是由粒度均匀的纳米颗粒组成的合金薄膜。     

纳米碳/纳米金葡萄糖生物传感器的制备及其影响机制

研究碳基纳米材料与纳米金(GNPs)颗粒的组合方式对葡萄糖(GLU)催化检测性能的影响。以离子液体(IL)作为导电性质的粘合剂,将碳基材料粘合在电极表面,并电沉积纳米金颗粒,制备成修饰电极。通过改变碳基种类(多壁碳纳米管(MWCNTs)、单壁碳纳米管(SWCNTs)、单壁碳纳米角(SWCNHs)、羧化石墨烯(C-GR))制备多种纳米碳修饰电极,对葡萄糖进行电化学检测和优化。实验发现,碳基材料性质影响葡萄糖传感器的灵敏度。其催化效果是MWCNTsSWCNTsC-GRSWCNHs,结果显示纳米材料电子加速通道对其催化性能起关键作用,碳基修饰层上电沉积的单层纳米金对葡萄糖的检测灵敏。通过SEM表征发现,相比于裸玻碳电极(GCE),纳米碳管上电沉积的纳米金颗粒尺寸更微小,且分散在碳纳米管上。组合有利于碳基与纳米金颗粒催化效应的发挥。制备了一种高灵敏无酶葡萄糖传感器,并尝试用于实际血清加标回收检测。     

生物质碳气凝胶/MnO2复合电极对 Rb+、Cs+的电吸附行为

以柚子皮为主要原料,采用低温水热碳化-真空冷冻干燥-高温碳化相结合的方法,制备了生物质碳气凝胶（PCA）,并将其用于制备PCA单一和PCA@MnO2（MPCA）复合电吸附电极,利用SEM、XRD、FT-IR、BET及电化学工作站对电极材料的形貌、结构和电化学性质进行了表征,并考察了两种电极对Rb+、Cs+的电吸附行为。结果表明,自制PCA为三维多孔结构,利于吸附质扩散;电极比电容大,循环性能好。电极的组成对电吸附行为具有较大的影响,二氧化锰的加入改变了电极对离子的吸附选择性,MPCA［m（二氧化锰）∶m（PCA）=4∶1］复合电极对铷的吸附量明显优于铯,平衡吸附量分别可以达到85 μmol/g和64 μmol/g,优于PCA电极,且具有良好的循环再生性能。     

Carbon nanotube array anodes for high-rate Li-ion batteries

The electrochemical performance of carbon nanotube array (CNTA) and entangled carbon nanotube (ECNT) electrodes are studied as anodes for Li-ion batteries. CNTA anodes display higher capacity (373 mAh g⁻¹) and much better rate and cycle performances than ECNT anodes. The performance of CNTA electrode shows length dependencies, i.e., shorter CNTA electrodes present higher specific capacity and better rate performance. The energy storage characteristics of CNTA electrodes are discussed on the basis of experimental results of SEM, TEM, and Raman spectra. The inner graphene layers of CNTs in CNTA electrode, which can form electron conductive paths and ensure a high conductivity, are retained during Li-ion insertion/extraction. These mechanically robust inner graphene layers can avoid the loss of outer active materials during Li-ion insertion/extraction, which, in turn, results in a good cycle performance.     

石墨烯/聚苯胺修饰阳极对微生物燃料电池性能的影响

纳米材料修饰阳极可显著提高微生物燃料电池（MFC）性能,本研究主要探索了石墨烯、聚苯胺和石墨烯/聚苯胺复合修饰电极对MFC产电性能的影响。使用电化学方法电镀石墨烯于碳布表面,进一步通过原位聚合法制备聚苯胺来修饰碳布电极。将修饰电极装载入双室型MFC中,测量其产电性能,并对电极进行表征,测量电化学性能。通过扫描电镜观察到, 碳布能够被修饰上石墨烯和聚苯胺,并且聚苯胺附着于碳纤维或石墨烯薄层表面,形成棒状的纳米结构。产电性能方面,装载石墨烯/聚苯胺修饰电极的MFC最大输出电压最高,达到了（291±22）mV,比装载空白碳布电极的对照组MFC提高了175%以上。石墨烯/聚苯胺电极组MFC的最大输出功率密度同样最高,达到了（653 ± 25）mW·m^-2,为空白碳布对照组的10.5倍。实验结果表明：石墨烯/聚苯胺复合修饰电极可有效利用石墨烯导电性好和聚苯胺生物相容性高的优点,显著提高MFC的产电性能。     

Carbon nanotube/graphene composite for enhanced capacitive deionization performance

In this study, single-walled carbon nanotubes were combined with graphene oxide nanosheets in aqueous dispersion and then chemically reduced to form the carbon nanotube/graphene (CNT/G) composite as electrodes for capacitive deionization (CDI). The structure of the CNT/G composite was highly porous, with single-walled carbon nanotubes (SWCNTs) sandwiched between graphene sheets that functioned as spacers and provided diffusion paths for smooth and rapid ion conduction. The associated increase in the electrical double-layer capacitance enhanced capacitive deionization performance. The CNT/G composite achieved a specific capacitance of 220 F/g and an electrosorption capacity of 26.42 mg/g with 100% regeneration, showing great potential as a high performance electrode material in CDI applications.     

Double-layer capacity measurements as a method to characterize porous fuel cell electrodes

Growing interest in porous Teflon-bonded carbon and catalyst carbon electrodes has resulted in increasing research efforts to improve performance and lifetime of these electrodes. The impedance method is demonstrated as a useful instrument to investigate these semihydrophobic electrodes. The double-layer capacity, derived by rather simple calculations from impedance spectra, is correlated with important parameters such as Teflon content, fabrication pressure and drying temperature of the electrode as well as to the deterioration processes which are still limiting the lifetime of the electrode. Information needed for improving these electrodes can be deduced from C_D measurements. Further interpretation of the impedance spectra and calculation of kinetic data are possible with the aid of appropriate equivalent circuits.     

Electroadsorption of Colloids on Electrodes

Abstract

The electrically induced adsorption of suspended colloidal particles on charged electrodes is studied by the HHF-Hamaker theory. Surface potentials are calculated by the Gouy-Chapman model for a diffuse double layer. Particle-particle and particle-surface interaction energies are compared for several cases of surface-to-particle charge density ratios. It is shown that electroadsorption of colloidal particles is hindered when their surface charge density is larger then that of the electrode.     

In vitro recording of neural activity using carbon nanosheet microelectrodes

The advent of nanotechnology has revolutionised our ability to engineer electrode interfaces. These are particularly attractive to measure biopotentials, and to study the nervous system. In this work, we demonstrate enhanced in vitro recording of neuronal activity using electrodes decorated with carbon nanosheets (CNSs). This material comprises of vertically aligned, free standing conductive sheets of only a few graphene layers with a high surface-area-to-volume ratio, which makes them an interesting material for biomedical electrodes. Further, compared to carbon nanotubes, CNSs can be synthesised without the need for metallic catalysts like Ni, Co or Fe, thereby reducing potential cytotoxicity risks. Electrochemical measurements show a five times higher charge storage capacity, and an almost ten times higher double layer capacitance as compared to TiN. In vitro experiments were performed by culturing primary hippocampal neurons from mice on micropatterned electrodes. Neurophysiological recordings exhibited high signal-to-noise ratios of 6.4, which is a twofold improvement over standard TiN electrodes under the same conditions.     

Comment on “Carbon nanotube/graphene composite for enhanced capacitive deionization performance” by Y. Wimalasiri and L. Zou

In a recent study, Wimalasiri and Zou [1] have reported the use and performance of composite electrodes of carbon nanotubes (CNT) and graphene for application as porous electrodes in capacitive deionization (CDI). While CDI is emerging as an attractive technology for water desalination, and novel electrode materials and composites are important contributions to the advancement of the field, there are several issues in this study that we must comment on.     

Facile precipitation of tin oxide nanoparticles on graphene sheet by liquid phase plasma method for enhanced electrochemical properties

A high-performance lithium ion battery (LIB) electrode was prepared by precipitating tin oxide nanoparticles on graphene powder by the liquid phase plasma (LPP) method. The particles generated by the LPP reaction are spherical SnO₂ nanoparticles with a size of 5-10 nm, as confirmed by a variety of analytical devices. The quantity of SnO₂ nanoparticles partially aggregated on the graphene sheet surface increases as the initial concentration of the tin precursor increases. The SnO₂/graphene nanocomposites (SGNC) electrodes prepared by the LPP method demonstrated improved cycling stability and reversible lithium storage capacity as compared to the bare graphene electrode. The precipitated tin oxide improves the lithium storage capacity, but excess tin oxide nanoparticles rather reduced the cycling stability.