Nanotechnology Applications in Water Disinfection

Nanotechnology has emerged as a transformative approach to water disinfection, harnessing the unique physicochemical properties of materials at the nanoscale to inactivate pathogens and degrade organic contaminants. Metallic nanoparticles—particularly silver, copper and titanium dioxide—exert potent antimicrobial action through mechanisms such as ion release, generation of reactive oxygen species and direct contact with microbial membranes. Composite materials combining magnetic, ceramic or polymeric supports with embedded nanoparticles offer advantages in recoverability, stability and controlled release. Nanostructured photocatalysts exploit ultraviolet or visible light to produce oxidative radicals capable of mineralising organic pollutants and inactivating bacteria and viruses. Recent advances focus on the integration of nanocellulose, zeolitic or activated-carbon scaffolds to achieve high surface area, enhanced dispersibility and tunable porosity. Point-of-use devices employing gravity-driven or membrane-based filtration enable decentralised provision of microbiologically safe water. Across laboratory and field studies, nanomaterials have demonstrated rapid microbial inactivation, multi-log reduction of bacteria and viruses, and sustained performance over multiple treatment cycles. Challenges remain in ensuring environmental safety, minimising metal leaching and elucidating long-term impacts, but ongoing research is paving the way towards scalable, cost-effective and robust nanotechnology-based water treatment solutions with global relevance.

Research from Nature Portfolio

Studies have demonstrated low-cost nanocellulose–aluminium oxyhydroxide composites functionalised with immobilised silver nanoparticles for point-of-use water disinfection. By probing chloride concentrations typical of freshwaters, researchers have shown that antibacterial performance against Escherichia coli and Bacillus subtilis declines markedly as chloride levels rise from 10 to 290 ppm. A one-hour contact time achieved up to 5.6 log10 reduction at low chloride, but only 2.2 log10 at high chloride, underscoring the need to tailor silver-releasing materials to local water chemistry for optimal efficacy.

Nanotechnology Applications in Water Disinfection publication trend

The graph below shows the total number of articles in nanotechnology applications in water disinfection across all publications each year (not limited to Nature Index journals).

Technical terms

Nanocomposite: A hybrid material in which nanoparticles are dispersed within a supporting matrix to combine functional properties.

Nanocellulose: Cellulose engineered at the nanoscale, offering high surface area and mechanical strength for composite scaffolds.

Log reduction: A measure of disinfection efficacy indicating tenfold (one-log) decreases in microbial concentration.

Surface plasmon resonance: Collective oscillation of conduction electrons in metallic nanoparticles, exploited for enhanced antimicrobial or photocatalytic activity.

References

1. Effects of Chloride Concentration on the Water Disinfection Performance of Silver Containing Nanocellulose-based Composites. Scientific Reports (2019).
2. Well-Dispersed Silver Nanoparticles on Cellulose Filter Paper for Bacterial Removal. Nanomaterials (2021).
3. Inactivation of RNA and DNA viruses in water by copper and silver ions and their synergistic effect. Water Research X (2020).
4. Magnetically Recoverable and Reusable Antimicrobial Nanocomposite Based on Activated Carbon, Magnetite Nanoparticles, and Silver Nanoparticles for Water Disinfection. Inventions (2017).