Environmental nanotechnology:
- Sustainable development towards next-generation of multifunctional nanostructures; Application in 1) adsorption, 2) resource recovery, 3) chemical oxidation, 4) sono/photocatalytic (visible and UV light) oxidation, and 5) soil and groundwater remediation.

Membrane fouling mitigation:
- Design and optimization of innovative physicochemical separation processes (ultrafiltration and nanofiltration) for drinking water and industrial wastewater treatment in terms of energy consumption and concentrate management.

Fate and transport of nanomaterials:
- Characterization of the environmental fate processes of engineered and natural nanomaterials (contaminant fate and transport in the subsurface); Transformations, reactivity, and toxicity of nanoparticles in soils, water, and plants.