Photocatalytic activity of polyaniline and neutral polyaniline for degradation of methylene blue and malachite green dyes under UV Light

Facile and green synthesis of ZnO nanoparticles for effective photocatalytic degradation of organic dyes and real textile wastewater

Remediation of organic dyes from wastewater in textile industries is a big challenge to decreasing water pollution. This study was aimed at the preparation of ZnO nanoparticles (NPs) and their application as a photocatalyst for the degradation of methylene blue (MB), sunfix red (SR) and real textile wastewater (RTW) under both UV and visible irradiations. The ZnO NPs were synthesized with a green Thymus vulgaris leaf extract-supported approach following the calcination process. 50 mg L^-1 MB and 50 mg L^-1 SR dyes were completely photodegrade under UV irradiation after only 20 and 45 minutes, respectively, in the presence of 1.0 mg/mL ZnO NPs. When they are exposed to visible light, the degradation efficiency reached 91 and 75% within 60 and 120 min, respectively. Photocatalytic measurements of RTW depict that 95% (within 60 min under UV illumination) and 79% (within 90 min under visible illumination) were degraded, respectively. The enhanced photodegradation can be attributed to the narrowing of the bandgap of the ZnO NPs, high crystallinity and nearly hexagonal morphology with an average size of 20-30 nm. The present results show that ZnO NPs could potentially be applied for high-efficiency degradation of organic dyes and RTW under both UV and visible light irradiation.

Recent Advances in the Removal of Organic Dyes from Aqueous Media with Conducting Polymers, Polyaniline and Polypyrrole, and Their Composites

Water pollution by organic dyes, and its remediation, is an important environmental issue associated with ever-increasing scientific interest. Conducting polymers have recently come to the forefront as advanced agents for removing dye. The present review reports on the progress represented by the literature published in 2020–2022 on the application of conducting polymers and their composites in the removal of dyes from aqueous media. Two composites, incorporating the most important polymers, polyaniline, and polypyrrole, have been used as efficient dye adsorbents or photocatalysts of dye decomposition. The recent application trends are outlined, and future uses also exploiting the electrical and electrochemical properties of conducting polymers are offered.

Role of polyaniline in accomplishing a sustainable environment: recent trends in polyaniline for eradicating hazardous pollutants

Attaining a sustainable environment has become a prime area of research interest, as it is an utmost necessity for a healthy life. Hence, ample studies have been carried out in adopting different processes and utilizing various materials to attain the goal. Herein, we present an exclusive discussion on one such material, i.e., polyaniline (PANI) and its derivatives. Being an intrinsic conducting type, it has grabbed more attention due to its durability in different doped/un-doped states, promptness in structural alteration, and solution processability. This review presents an exhaustive discussion on published reports showing utilization of PANI and its derivative in various forms like pure and composites, for cleaning the environment through adsorption, photodegradation, etc., and the various methods adopted in order to achieve an optimum operating condition to obtain the maximum outcome. In addition to these merits and demerits, various technical challenges faced with materials have been also presented. Therefore, it is expected that this piece of work, presenting the exhaustive discussion on PANI and; its derivatives would help to develop a better understanding of this excellent conducting polymer PANI and provide a state of art on the role of this material for attaining sustainable surroundings for the living beings.