Processable dodecylbenzene sulfonic acid (DBSA) doped poly(N-vinyl carbazole)-poly(pyrrole) for optoelectronic applications

Synthesis of Highly Conductive Poly(3-hexylthiophene) by Chemical Oxidative Polymerization Using Surfactant Templates

Poly(3-hexylthiophene) (P3HT) was systematically synthesized by chemical oxidative polymerization in chloroform with ferric chloride (FeCl₃) as the oxidizing agent and various surfactants of the shape templates. The effects of 3HT: FeCl₃ mole ratios, polymerization times, and surfactant types and concentrations on the electrical conductivity, particle shape and size were systematically investigated. Furthermore, dodecylbenzenesulfonic acid (DBSA), p-toluenesulfonic acid (PTSA), sodium dodecyl sulfate (SDS), and sodium dioctyl sulfosuccinate (AOT) were utilized as the surfactant templates. The P3HT synthesized with DBSA at 6 CMC, where CMC stands for the Critical Micelle Concentration of surfactant, provided a higher electrical conductivity than those with PTSA, SDS and AOT. The highest electrical conductivity of P3HT using DBSA was 16.21 ± 1.55 S cm⁻¹ in which the P3HT particle shape was spherical with an average size of 1530 ± 227 nm. The thermal analysis indicated that the P3HT synthesized with the surfactants yielded higher stability and char yields than that of P3HT without. The P3HT_DBSA electrical conductivity was further enhanced by de-doping and doping with HClO₄. At the 10:1 doping mole ratio, the electrical conductivity of dP3HT_DBSA increased by one order of magnitude relative to P3HT_DBSA prior to the de-doping. The highest electrical conductivity of dP3HT_DBSA obtained was 172 ± 5.21 S cm⁻¹ which is the highest value relative to previously reported.

Conductive polymers to modulate the post-stroke neural environment

Despite the prevalence of stroke, therapies to augment recovery remain limited. Here we focus on the use of conductive polymers for cell delivery, drug release, and electrical stimulation to optimize the post-stroke environment for neural recovery. Conductive polymers and their interactions with in vitro and in vivo neural systems are explored. The ability to continuously modify the neural environment utilizing conductive polymers provides applications in directing stem cell differentiation and increasing neural repair. This exciting class of polymers offers new approaches to optimizing the post-stroke brain to improve functional recovery.

A Review on the Advancement of Ternary Alloy Counter Electrodes for Use in Dye-Sensitised Solar Cells

A dye-sensitised solar cell (DSSC) counter electrode (CE) plays a vital role in catalysing the conversion of triiodide ( I 3 − ) to iodide ions ( I − ), thereby ensuring the completion of the repetitive cycle of electricity generation. The platinum CE, despite being the standard counter electrode in DSSCs, has drawbacks of platinum’s rarity and high cost. Platinum is an excellent redox catalyst, and consequently, it is the most sought-after metal for catalytic conversions. The huge demand for platinum in the automotive industry for vehicular catalytic converters, the pharmaceutical industry, and in oil refining, as well as other industries, has driven its price to unprecedented levels. The prohibitive price of platinum has caused newer thin film technologies, such as the DSSC which depends on the platinum CE, to be cost-ineffective, thus meaning they cannot compete with the better-established silicon-based solar cells. These problems have stagnated the development of the DSSC, which in turn has dampened larger commercialisation prospects for this thin film technology. With this in mind, this review paper focuses on recent progress in the research and development of alternative cost-effective materials to replace Pt-based CEs. Ternary alloys are amongst the possible alternatives that have been explored, yielding varied results. Alloys, especially ternary sulphides, selenides, and oxides, are attractive as alternatives as they are cheap and are easily fabricated. Ternary alloys also have a synergistic effect produced by the coexistence of two metal ions in a crystal structure, which is believed to induce greater catalytic capability, thus making them ideal cost-effective materials to replace the Pt CE in DSSCs. This review intends to highlight the performance of ternary alloy counter electrodes through the analysis of charge transfer resistance and power conversion efficiencies. Focus is also given to the restrictions and impediments to the attainment of higher power conversion efficiency in alternative CEs. The advances in fabrication of simple ternary alloys, as well as more advanced hierarchical nanostructured counter electrodes, are discussed here in detail. Results obtained to date indicate that the efficiencies of ternary alloy counter electrodes are still below that of the platinum counter electrode, and hence more research is required to enhance their efficiencies.

Facile Preparation of Doxorubicin-Loaded and Folic Acid-Conjugated Carbon Nanotubes@Poly(N-vinyl pyrrole) for Targeted Synergistic Chemo-Photothermal Cancer Treatment

We developed a bifunctional nanoplatform for targeted synergistic chemo-photothermal cancer treatment. The nanoplatform was constructed through a facile method in which poly(N-vinyl pyrrole) (PVPy) was coated on cut multiwalled carbon nanotubes (c-MWNTs); FA-PEG-SH was then linked by thiol-ene click reaction to improve the active targeting ability, water dispersibility, and biocompatibility and to extend the circulation time in blood. The PVPy shell not only enhanced the photothermal effect of c-MWNTs significantly but also provided a surface that could tailor targeting molecules and drugs. The resulting MWNT@PVPy-S-PEG-FA possessed high drug-loading ratio as well as pH-sensitive unloading capacity for a broad-spectrum anticancer agent, doxorubicin. Owing to its outstanding efficiency in photothermal conversion and ability in targeted drug delivery, the material could potentially be used as an efficient chemo-photothermal therapeutic nanoagent to treat cancer.