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In this present study, we report a facile microwave assisted green synthesis of ZnO/Ag nanocomposites (denoted as G‐ZnO/Ag NCs) by employing Tridax procumbens leaf extract as a green solvent for photocatalytic, antimicrobial and cytotoxicity activities. The prepared nanocomposites was characterized by various techniques to study its crystallinity, morphology, structure, chemical composition, optical properties, and so on. The nanocomposites exhibited excellent photocatalytic performance (90.2 %) toward methylene blue degradation when irradiated under visible light (120 min). Furthermore, the G‐ZnO/Ag NCs showed good reusable properties up to four consecutive cycles. In addition, the resultant nanocomposites showed significant antimicrobial activity with the zones of inhibition of 9.85±0.12 and 10.51±0.63 mm against gram positive (Staphylococcus aureus) and 11.98±0.22 and 13.76±0.12 mm against gram‐negative (Escherichia coli), bacteria respectively, as measured using the well diffusion method. Although, the in‐vitro cytotoxicity test showed 39.58 % viability of MCF‐7 cells. In summary, this study suggest that G‐ZnO/Ag NCs as a promising tool for wastewater treatment and nano biomedical applications using low cost and eco‐friendly approach.

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The growing demand and use of geopolymer binders have been of high interest in recent times due to their sustainability and economic bene ts. However, locally available materials must be used in the production of geopolymer binders in order to maximize their bene ts. In this study, a laterite soil which is a locally available material in many parts of the world was used as the aluminosilicate precursor. In order to produce the geopolymer binders, the laterite soil was activated thermally through calcination and the resulting calcined laterite was activated with an alkali activator composed of sodium hydroxide (NaOH) and sodium silicate (Na 2 SiO 3 ). The in uence of calcination temperature and the concentration of NaOH on the properties of the developed geopolymers was investigated. Calcination temperature used ranged between 550 °C to 750 °C and the NaOH concentrations used were 8 M and 10 M. The results from this study indicate that some locally available laterite soils can be utilized in the production of geopolymer binders if they undergo calcination. Increasing the calcination temperature from 550 °C to 750 °C resulted in the transformation of phases and an increase in the reactivity of the laterites, resulting in material with improved properties. The use of laterite calcined at 750 °C and activated with 8 M NaOH solution resulted to an increase in the 28 days compressive strength by 35.3 MPa compared to when laterite calcined at 550 °C was used. Increasing the concentration of the NaOH solution was also found to yield higher material performance. Microstructural investigations were also carried out to con rm the macrostructural properties.