导电炭黑微观结构及其应用性能

以乙炔炭黑、副产炭黑和炉法导电炭黑为研究对象,较为系统地分析了与导电炭黑应用性能密切相关的微晶结构、表面性质、颗粒形貌和粒度分布特征,探讨了导电炭黑微观结构对应用性能的影响。研究结果表明,导电炭黑的微观结构决定了其应用性能,而决定应用性能的关键在于其与基体材料的匹配性。副产炭黑在橡胶和塑料中导电性能较好,乙炔炭黑在锂离子电极材料中的导电性能较好。     

Improvement of the adhesion between polyaniline and commercial carbon paper by acid treatment and its application in supercapacitor electrodes

Commercial carbon paper was coated with polyaniline (PANI) using in situ polymerization of aniline. Prior to the PANI coating, acid treatment was performed to carboxylate the surface of the carbon paper for enhancing PANI adhesion by sonication of the carbon paper in a mixture of concentrated sulfuric and nitric acids. The loading mass density of PANI on the acid-treated carbon paper increased more than three times compared to that on the carbon paper without acid treatment. The specific capacitance also increased from 112 to 174 F/g in a two-electrode system (calculated using a total mass of carbon paper and PANI) due to better PANI coating on the acid-treated carbon paper. The simple acid treatment provides good adhesion of PANI to the commercial carbon paper and can be applied to prepare supercapacitor electrodes.     

Radiofrequency plasma beam deposition of various forms of carbon based thin films and their characterization

The characteristics of carbonic materials obtained by downstream deposition in a low pressure argon plasma beam injected with acetylene are reported. The influence of substrate temperature, presence of Ni catalyst and hydrogen in gas composition on the material properties is described. By increasing the substrate temperature, an enhanced order in the material is revealed by Raman spectroscopy, while FTIR measurements show a decreasing of the hydrogen content and the disappearing of sp¹ hybridized carbon in the deposit. The SEM and Raman investigation show a clear tendency of crystalline phases formation when hydrogen is assisting the deposition.     

Different configurations of transferred atmospheric pressure plasma jet and their application to polymer treatment

The employment of atmospheric pressure plasma jets (APPJs) in a large sort of applications is limited by the adversities related to the size of the treated area and the difficulty to reach the target. The use of devices that employ long tubes in their structure has contributed significantly to overcome these challenges. In this work, two different plasma systems employing the jet transfer technique are compared. The main difference between the two devices is how the long plastic tube was assembled. The first one uses a copper wire placed inside a long plastic tube. The other device has a metallic mesh installed in a concentric arrangement between two coaxial plastic tubes. As a result, the two APPJ systems exhibit different properties, with the wire assembly being more powerful, also presenting higher values for the electrical current and rotational temperature when compared to the mesh mounting. X-ray photoelectron spectroscopy (XPS) demonstrates that both configurations were capable of inserting O-containing functional groups on the polypropylene (PP) surface. However, the transferred plasma jet with wire assembly was able to add more functional groups on the PP surface. The results from XPS analysis were corroborated with water contact angle measurements (WCA), being that lower WCA values were obtained when the PP surface presented higher amounts of O-containing groups. Furthermore, the results suggest that the APPJ with wire configuration is more appropriate for material treatments, while the transferred jet with mesh arrangement tends to present lower electrical current values, being more suitable for biological applications.     

A simple synthesis method to produce metal oxide loaded carbon paper using bacterial cellulose gel and characterization of its electrochemical behavior in an aqueous electrolyte

A simple synthetic chemical process to produce metal oxide loaded carbon papers was developed using bacterial cellulose gel, which consisted of nanometer-sized fibrous cellulose and water. Metal ions were successfully impregnated into the gel via aqueous solution media before drying and carbonization methods resulting in metal oxide contents that were easy to control through variations in the concentration of aqueous solutions. The papers loaded by molybdenum oxides were characterized as pseudocapacitor electrodes preliminary, and the large redox capacitance of the oxides was followed by a conductive fibrous carbon substrate, suggesting that a binder and carbon black additive-free electrode consisting of metal oxides and carbon paper was formed.     

Effects of O2 and N2/H2 plasma treatments on the neuronal cell growth on single-walled carbon nanotube paper scaffolds

The O₂ and N₂/H₂ plasma treatments of single-walled carbon nanotube (SWCNT) papers as scaffolds for enhanced neuronal cell growth were conducted to functionalize their surfaces with different functional groups and to roughen their surfaces. To evaluate the effects of the surface roughness and functionalization modifications of the SWCNT papers, we investigated the neuronal morphology, mitochondrial membrane potential, and acetylcholine/acetylcholinesterase levels of human neuroblastoma during SH-SY5Y cell growth on the treated SWCNT papers. Our results demonstrated that the plasma-chemical functionalization caused changes in the surface charge states with functional groups with negative and positive charges and then the increased surface roughness enhanced neuronal cell adhesion, mitochondrial membrane potential, and the level of neurotransmitter in vitro. The cell adhesion and mitochondrial membrane potential on the negatively charged SWCNT papers were improved more than on the positively charged SWCNT papers. Also, measurements of the neurotransmitter level showed an enhanced acetylcholine level on the negatively charged SWCNT papers compared to the positively charged SWCNT papers.