Abstract: A gravity-fed storage water purifier is provided. The gravity-fed water purifier includes a filtration unit for receiving water. The filtration unit includes a housing unit, a first membrane cloth layer, a second membrane cloth layer, and a granular biocidal composition layer disposed between the first and second membrane cloth layers. The first and second membrane cloth layers remove dirt, sand and sediments from the contaminated water, using a depth filtration mechanism. The granular biocidal composition layer removes bacteria and virus from the contaminated water, through fast leaching of silver ions into the water. A single storage container is provided that collects the water filtered by the virtue of filtration unit and gravity. An adsorbent composition is disposed between the storage container and an outlet tap of the storage container.

Abstract: The preparation of silver quantum clusters embedded in organic-templated-boehmite-nanoarchitecture (OTBN) and its use as a sensor for quantity of water flow measured by change of color in visible light upon flow of contaminated water have been provided. Silver quantum clusters-embedded OTBN are highly luminescent. Since the quantum clusters are embedded in the matrix, they are highly stable over a long period of time. The composition described here is utilized in the form of a device for ‘visible/ultraviolet light color change-based detection’ upon passage of water through a water purification device. Upon interaction with ions present in water, luminescent silver clusters undergo chemical transformation to Ag2S nanoparticles. The transformation is reflected in the form of visible color change (from pink to black) and luminescence quenching (from red emission to negligible luminescence).

Abstract: An adsorbent composition comprising a nanoscale shell of metal oxide or hydroxide on an organic-templated-boehmite-nanoarchitecture (OTBN) is provided. The nanoscale shell is prepared by impregnating OTBN with a metal or a non-metal ion, followed by in-situ hydrolysis of the deposited ion on the OTBN surface. The thickness of the shell is less than about 3 nm, which is less than the size of OTBN core. The number of layers of the shell is flexible, thereby leading to a multi-layer nanoscale hybrid composition. The adsorbent composition is capable of removing inorganic anions such as fluoride from water, with an increased adsorption capacity.

Abstract: Described herein are methods and compositions for preparing an adsorbent composition for sustained silver ion release is provided. The method comprises impregnating silver nanoparticles on an organic-templated-nanometal oxyhydroxide. Particle size of the silver nanoparticles is less than about 50 nm. The adsorbent composition is antimicrobial in water. In an aspect, the organic-templated-nanometal oxyhydroxide is organic-templated-boehmite nanoarchitecture (OTBN). The resultant adsorbent composition is used as a water filter in a water purification device.

Abstract: A composition for the purification of water and the device using the composition, where the composition contains a transition metal ion Mn+ releasing compound along with an CO32? releasing compound or an SiO32? releasing compound.

Abstract: The preparation of silver quantum clusters embedded in organic-templated-boehmite-nanoarchitecture (OTBN) and its use as a sensor for quantity of water flow measured by change of color in visible light upon flow of contaminated water have been provided. Silver quantum clusters-embedded OTBN are highly luminescent. Since the quantum clusters are embedded in the matrix, they are highly stable over a long period of time. The composition described here is utilized in the form of a device for ‘visible/ultraviolet light color change-based detection’ upon passage of water through a water purification device. Upon interaction with ions present in water, luminescent silver clusters undergo chemical transformation to Ag2S nanoparticles. The transformation is reflected in the form of visible color change (from pink to black) and luminescence quenching (from red emission to negligible luminescence).

Abstract: An adsorbent composition comprising a nanoscale shell of metal oxide or hydroxide on an organic-templated-boehmite-nanoarchitecture (OTBN) is provided. The nanoscale shell is prepared by impregnating OTBN with a metal or a non-metal ion, followed by in-situ hydrolysis of the deposited ion on the OTBN surface. The thickness of the shell is less than about 3 nm, which is less than the size of OTBN core. The number of layers of the shell is flexible, thereby leading to a multi-layer nanoscale hybrid composition. The adsorbent composition is capable of removing inorganic anions such as fluoride from water, with an increased adsorption capacity.

Abstract: A gravity-fed storage water purifier is provided. The gravity-fed water purifier includes a filtration unit for receiving water. The filtration unit includes a housing unit, a first membrane cloth layer, a second membrane cloth layer, and a granular biocidal composition layer disposed between the first and second membrane cloth layers. The first and second membrane cloth layers remove dirt, sand and sediments from the contaminated water, using a depth filtration mechanism. The granular biocidal composition layer removes bacteria and virus from the contaminated water, through fast leaching of silver ions into the water. A single storage container is provided that collects the water filtered by the virtue of filtration unit and gravity. An adsorbent composition is disposed between the storage container and an outlet tap of the storage container.

Abstract: Described herein are methods and compositions for preparing an adsorbent composition for sustained silver ion release is provided. The method comprises impregnating silver nanoparticles on an organic-templated-nanometal oxyhydroxide. Particle size of the silver nanoparticles is less than about 50 nm. The adsorbent composition is antimicrobial in water. In an aspect, the organic- templated-nanometal oxyhydroxide is organic-templated-boehmite nanoarchitecture (OTBN). The resultant adsorbent composition is used as a water filter in a water purification device.

Abstract: A gravity-fed, axial flow filtration system for treating water is disclosed.

Abstract: Disclosed are granular composites comprising a biopolymer and one or more nanometal-oxyhydroxide/hydroxide/oxide particles, along with methods for the preparation and use thereof.