Synthesis of nanoparticles (NPs) and nanomaterials (NMs) has attracted considerable attention in recent past due to its multi-faceted importance across various domains most importantly in terms of environmental sustainability, biocompatibility, safety, economic viability, attainment of novel properties in the synthesized NPs and NMs. The unique properties at the nanoscale of these synthesized NMs have sparked a revolution in research and have significantly impacted our daily lives in numerous ways such as in medicine (targeted drug delivery, diagnostics, etc.), electronics (smaller and more efficient devices), energy (Improved solar cells, batteries, and fuel cells), environmental remediation (efficient pollution control and water purification) and consumer products (sunscreens, clothing, etc.). Characterization of synthesized NPs and NMs is very important because the unique properties exhibited by NMs and NPs are heavily influenced by their size, shape, composition, and surface characteristics. Although a broad toolkit (UV-Vis, FTIR, XRD, SEM, TEM, AFM, SAED, EDX and Zeta potential measurements) is required for full nanoparticle characterization, FTIR provides unique, chemically specific information on molecular bonding, surface functional groups and adsorbed species that complements structural, morphological and surface-charge measurements provided by the other techniques. In this review article, use of FTIR in the characterization of NPs and NMs is discussed.

Zinc oxide is considered an effective photocatalyst for degradation of several organic contaminants found in wastewater. This work reports the biological synthesis of zinc oxide nanoparticles and its calcium nanocomposites to study the photocatalytic deterioration of two dyes, viz. Rhodamine B and Methylene blue, under natural sunlight. Nanoparticles were synthesized using zinc acetate and starch extracted from potato at pH 7–8. Potato starch acts as both a capping agent and a reducing agent. They were characterized spectroscopically via XRD, SEM, HR-TEM, EDAX and FT-IR techniques. Bean/spherical shaped ZnO NPs were obtained in the size range of 29–49 nm whereas calcium coating on ZnO decreased the particle size, i.e., 25–35 nm. Their photocatalytic ability to degrade Rhodamine B and Methylene blue was studied under natural sunlight and monitored using UV-Vis spectrophotometer. Synthesized ZnO nanoparticles and its calcium coated ZnO nanocomposites showed promising results in degradation of these dyes. Methylene blue was completely degraded in an hour at 8 mg of the sample. Although degradation of Rhodamine dye was slow, synthesized samples were effective catalysts as compared to the ones reported in the literature.

The advent of nanotechnology has helped in several invention in science & technology. Contamination of surface water, ground and soil by various industrial dyes causes several ecological problems. Zinc oxide nanoparticles as photocatalysts and semiconductor materials show unique physical properties at the nanoscale and can be used to solve these problems to some extent. In this paper, we synthesized ZnO NPs and calcium-coated ZnO nanoparticles using extract of beetroot and then, for industrial point of view, we studied the photocatalytic degradation of methylene blue and rhodamine B using sun as a natural light source (sunlight). We have synthesized calcium-coated ZnO nanocomposites with 20–50 nm particle size. Synthesized nanomaterials were characterized by using the different physio-chemical techniques such as - FT-IR, XRD, TEM, SEM, EDX and UV-spectrophotometer do their photocatalytic degradation.

Background: Biogenic fabrication of metal oxide nanoparticles has been gaining interest over conventional methods. Biological methods make use of plant materials and microbial agents as reducing as well as capping agents. The present work reports the biosynthesis of ZnO NPs from agricultural wastes produced in every household. Objective: A significant portion of municipal solid organic waste (MSOW) consists of agricultural waste. Utilization of this agricultural waste towards cleaning water of pathogens through the synthesis of nanoparticles has far-reaching implications, such as curbing soil pollution and water pollution. Method: Preliminary confirmation was done by the visual formation of a pale yellow/dirty white precipitate of ZnO NPs. These were further characterized by different spectroscopic techniques, such as FT-IR, SEM, EDAX, and HRTEM. Results: The HRTEM study revealed that NPs obtained had sizes between 30-52 nm. Fabricated ZnO NPs were analyzed for their antibacterial activity by disk diffusion method, and they exhibited striking antibacterial activity against E. coli and bacillus subtilis. Conclusion: Exploring the potential of waste and its conversion into a value-added product is a novel step. ZnO nanoparticles were successfully synthesized from agricultural wastes through an environmentally friendly synthetic route, and the synthesized ZnO NPs were found to be potent in inhibiting the growth of bacteria.

Fossil fuels are the main energy sources worldwide even today. But with the alarming pace at which fossil fuels are exhausting, there would be a need for sustainable and economically viable alternatives in the near future. Fossil fuels pose severe environmental threats like air pollution, soil pollution, global warming etc. It is reported that the utilization of algal biomass to produce bioenergy could be one of the solutions. Microalgae offer many unique features with the potential to store lipids in their cells just like plant oils, CO2 sequestering capability, low space requirement, rapid growth, ability to grow in wastewater and rich in lipid and carbohydrate content. Although an array of nutrients is required for an algal bloom that could be fulfilled by nutrients from wastewater. In a way, it is the biological wastewater treatment technology producing green energy (WtE). Methods like supercritical fluid extraction, microwave and ultrasonic-assisted extraction, and Soxhlet extraction could be used for the microalgal lipid extraction. So, this chapter explores the possible methods to isolate lipids from biomass and their energy utilization.

Nanomaterials (NMs) particularly synthesized by green routes have attracted researchers and scientists for their multifunctional industrial applications. NMs have not only revolutionized research, but also our daily life because of numerous applications in medical diagnostics, consumer products, and energy-related applications. Their unique properties are directly related to chemical composition, structure, size and shape. There are several characterization techniques used to determine the size, composition, crystalline structure and other physical properties of NMs. Prominent among them are spectroscopic techniques such as UV-Visible, FTIR, EDX; diffraction techniques such as XRD, SAED; microscopic techniques such as SEM, TEM, AFM and others such as Zeta potential measurements. Every technique has its own merit and demerit. This mini review describes the uses of UV-Vis spectroscopy in characterization of NMs.

Medicines are the imperative constituent in the present day lifestyle and their consumption for different cause's increases day by day. Synthesis of most of the drugs involves use of toxic chemicals and hazardous solvents, tedious workup or lengthy strategies. The needs of environment friendly procedures are the prerequisites of current environment concern. The known drug candidates Sildenafil citrate and Celecoxib are selected for the investigation and study for improved synthetic opportunities. It is found that several alterations are useful in the synthesis of these biological active profiles and they are adopted for large scale production of the compound in pharmaceutical industries. The old and new synthetic strategies are discussed in this case study based article. Copyright (C) 2022 Elsevier Ltd. All rights reserved.

Uncoated ZnO and calcium-coated ZnO nanoparticles (Ca-ZnO) were biologically synthesized using cucumber juice as a reducing and capping agent. Cucumber belongs to Cucurbitaceae family, is rich in water content and possesses antioxidant activity. The chemical composition and morphology of the synthesized NPs were determined by scanning electron microscopy (SEM), energy dispersive X-ray spectrophotometer (EDS), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD)and FT-IR. The spherical as well as hexagonal-shaped ZnO nanoparticles were obtained in the size range of 4-70 nm. Coated and uncoated ZnO nanoparticles were evaluated for their photo degradability of methylene blue (MB) and rhodamine B (RB) dyes. They showed nearly 100% photodegradation of methylene blue in lesser time, however, showed minimum degradation of rhodamine B dye. Calcium coating over ZnO NPs enhanced their photocatalytic properties.

The use of nanotechnology for drinking water purification becomes the emerging field around the world. Usually the nanoparticles are synthesized by variety of chemicals which are quite toxic, flammable in nature and their modes of working are unethical for mankind. The extensive application of the AgNP results in their inevitable release into the environment. Silver nanoparticle is known as excellent antimicrobial agents and therefore they could be used as alternative disinfectant agents. It was found that the aggregation of AgNPs depends on the properties of the background ions, such as Na+ and Ca2+ at different water chemistry conditions. The antimicrobial properties of AgNPs when coated with different organic compounds using natural water conditions. The results obtained showed that silver nanoparticles in surface water and ground water are stable. The composition of AgNPs - impregnated RO-filters and silver- impregnated RO-filters. This study was performed using different water chemistry condition and different manufacturing materials. The results showed that AgNPs- impregnated RO Water filters are more appropriate for this application due to the lesser amount of silver nitrate treated filters. The bacterial removal performance of the AgNPs-treated RO- Water filters and concentration of viable bacteria in the filters are dose-dependent on the amount of silver applied.