The immobilization of photocatalyst onto substrate has a great potential for energy-intensive separation to avoid the costly separation process and unwanted release of photocatalyst into the treated water. In this study, electrospun nanofiber composed of polyvinylidene fluoride (PVDF) with the immobilized ZnO, ZnO/Ag₂CO₃, ZnO/Ag₂CO₃/Ag₂O, and ZnO/Ag₂O photocatalysts were prepared via the electrospinning process. The immobilized ZnO and heterojunctioned ZnO in the PVDF electrospun nanofiber were proven via X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The electrospinning allowed high chemical binding of the nanofiber composite with good physical interaction between the photocatalyst and the electrospun nanofiber. AFM images obtained for the nanofibers were found to be rougher than that of the pristine PVDF electrospun nanofiber. Among the photocatalyst embedded, the immobilized ZnO/Ag₂CO₃/Ag₂O had endowed the nanofiber with an excellent photocatalytic activity and recyclability for the degradation of the RR120 under UV light irradiation. Based on the results, effective immobilization of ZnO/Ag₂CO₃/Ag₂O in PVDF nanofiber with 99.62% photodegradation in 300 min compared to PVDF-ZnO, PVDF-ZnO/Ag₂CO₃, and PVDF-ZnO/Ag₂O of 28.14%, 90.49%, and 96.34%, respectively. The effective ZnO/Ag₂CO₃/Ag₂O immobilization into polymers with affinity toward organic dye pollutants could both increase the efficiency and reduce the energy requirements for water treatment via the photocatalytic application.

Titanium dioxide, TiO₂nanoparticles are being utilized in various application of science and technology including membrane, medical, electrical and chemical field for their respective worth which generally attributed to the self-cleaning and photocatalytic ability, good band gap, an antibacterial as well as physical and chemical stability. As commonly known conventional TiO₂nanoparticles synthesized using chemicals as reducing agents has become accountable for various biological risks due to their general toxicity, thus engendering the serious concern in developing environment friendly processes. Naturally derived products, such as extracts of plants that composed of biomolecules, have been used intensively recently as a reductant agent, that also sometimes can be acting as capping agents after synthesis process. These natural biomolecules mostly consisted of polyphenols have been identified to be actively play a role in this biosynthesis of nanoparticles from any plants extract that able to form different shapes and sizes of nanoparticles with better surface reactive area, characteristic and properties. Therefore, biosynthesis can be considered as a driving force for the greener, safe and environmentally friendly for many applications that have used TiO₂particles either used as additive, purely or in composite form. The present review targets on the ‘greener’ routes of synthesis TiO₂nanoparticles with an emphasis on experimental conditions based on sustainable methodologies and also explores the huge plant diversity to be utilized. The use of ‘greener’ not only reduces the cost of synthesis but also minimizes the need of using hazardous chemicals and stimulates green synthesis. This review also focuses on aspects characteristic and properties that generated from the output of this green process that make it strongly applicable to certain applications as for binding of biomolecules, to the biosynthesized is significantly benefit to biomedical fields. It is expected that these outstanding findings will encourage researchers and attract newcomers to continue and extend the exploration of possibilities offered by nature and the design of innovative and safer methodologies towards the synthesis of nanomaterials, possessing desired features and exhibiting valuable properties that can be exploited in a profusion of fields.