Additive manufacturing of polyaniline-based materials: an opportunity for new designs and applications in energy and biotechnology

Efficient photocatalytic reactors via 3D printing: SLA fabrication and TiO2 hybrid materials

Additive Manufacturing (AM) was evaluated as a promising technology for constructing photocatalytic reactors due to its inherent ability to produce complex geometries with high precision and customization. In this work, a 3D structure was designed to achieve a good light distribution inside a cylindrical batch reactor and printed using the stereolithography (SLA) technique. A hybrid material composed of a commercial photoreactive resin (Formlabs Clear V4) and the benchmark photocatalyst TiO2 P25 Evonik (1 wt%) was prepared and characterized by scanning electron microscopy (SEM) and rheological and mechanical methods. To evaluate the photocatalytic activity of the materials, several experiments on the photocatalytic degradation of Rhodamine B (RhB) were carried out using the 3D printed structure. Its performance was assessed by monitoring the concentration at specific times. Overall, the results demonstrate a simple, cost-effective, and fast technique to immobilize catalysts used in photocatalytic applications.

Unveiling the potential of PANI@MnO2@rGO ternary nanocomposite in energy storage and gas sensing

The development of advanced materials for energy storage and gas sensing applications has gained significant attention in recent years. In this study, we synthesized and characterized PANI@MnO2@rGO ternary nanocomposites (NCs) to explore their potential in supercapacitors and gas sensing devices. The ternary NCs were synthesized through a multi-step process involving the hydrothermal synthesis of MnO2 nanoparticles, preparation of PANI@rGO composites and the assembly to the ternary PANI@MnO2@rGO ternary NCs. The structural, morphological, and compositional characteristics of the materials were thoroughly analyzed using techniques such as XRD, FESEM, TEM, FTIR, and Raman spectroscopy. In the realm of gas sensing, the ternary NCs exhibited excellent performance as NH3 gas sensors. The optimized operating temperature of 100 °C yielded a peak response of 15.56 towards 50 ppm NH3. The nanocomposites demonstrated fast response and recovery times of 6 s and 10 s, respectively, and displayed remarkable selectivity for NH3 gas over other tested gases. For supercapacitor applications, the electrochemical performance of the ternary NCs was evaluated using cyclic voltammetry and galvanostatic charge-discharge techniques. The composites exhibited pseudocapacitive behavior, with the capacitance reaching up to 185 F/g at 1 A/g and excellent capacitance retention of approximately 88.54% over 4000 charge-discharge cycles. The unique combination of rGO, PANI, and MnO2 nanoparticles in these ternary NCs offer synergistic advantages, showcasing their potential to address challenges in energy storage and gas sensing technologies.

Designing Electrical Stimulation Platforms for Neural Cell Cultivation Using Poly(aniline): Camphorsulfonic Acid

Electrical stimulation is a powerful strategy to improve the differentiation of neural stem cells into neurons. Such an approach can be implemented, in association with biomaterials and nanotechnology, for the development of new therapies for neurological diseases, including direct cell transplantation and the development of platforms for drug screening and disease progression evaluation. Poly(aniline):camphorsulfonic acid (PANI:CSA) is one of the most well-studied electroconductive polymers, capable of directing an externally applied electrical field to neural cells in culture. There are several examples in the literature on the development of PANI:CSA-based scaffolds and platforms for electrical stimulation, but no review has examined the fundamentals and physico-chemical determinants of PANI:CSA for the design of platforms for electrical stimulation. This review evaluates the current literature regarding the application of electrical stimulation to neural cells, specifically reviewing: (1) the fundamentals of bioelectricity and electrical stimulation; (2) the use of PANI:CSA-based systems for electrical stimulation of cell cultures; and (3) the development of scaffolds and setups to support the electrical stimulation of cells. Throughout this work, we critically evaluate the revised literature and provide a steppingstone for the clinical application of the electrical stimulation of cells using electroconductive PANI:CSA platforms/scaffolds.

Fabrication of Polyaniline/graphene oxide composites for implementing it in humidity sensing

This work reports the measurement of impedance variations under various humidity conditions at frequency ranges between 100 Hz to 5 MHz. The electrochemical polymerization process has been used to synthesize by varying the mass ratios of graphene oxide (GO) in polyaniline (PAni). The electrochemical deposition method has been used to make samples film on an Indium Tin Oxide (ITO) glass slide. The percentage relative humidity (RH) of the samples was estimated to be 20 to 90%. It has been found that impedance and humidity show an inverse relation, i.e., the impedance value decreases with an increase in humidity. In contrast with platitudinous capacitive humidity sensors (PC-HS), the GO-based humidity sensor has a sensitivity of 75 to 99%, which is approximately ten times more elevated than traditional sensors. It has been observed with three different paraments weight % of GO; the frequency ranges between 100 Hz to 5 MHz and RH % between 20 to 90%. Moreover, it has been demonstrated that the humidity sensor shows a fast response and recovery time. Therefore, GO appears to be a consummate material for building a humidity sensor with high sensing for a comprehensive approach.