Research Projects

#Motivation: India’s water crisis is worsening, with ~70% of surface water unfit for use due to industrial discharge from pharmaceuticals, textiles, and agriculture. These introduce emerging pollutants such as dyes, antibiotics, pesticides, and toxic metals like mercury (Hg²⁺), a potent neurotoxin released by e-waste, chlor-alkali units, and battery industries. Surveys show mercury, arsenic, and lead levels exceeding safety limits in 81 Indian rivers. Lab techniques like ICP-MS and chromatography are expensive, slow, and unsuitable for field use. Existing sensors often lack multifunctionality and durability in real samples. There is a pressing need for portable, low-cost materials capable of detecting and neutralizing trace contaminants on-site. #Scientific Objectives: We aim to develop a flexible, self-standing plasmonic-electroactive nanocomposite film for ultra-trace pollutant detection and remediation via both SERS and electrochemical methods. Objectives include: 1. Fabricate a Ti₃C₂Tₓ MXene film functionalized with glutathione (GSH) and embedded with plasmonic Ag/Au NPs in a PEDOT:PSS polymer matrix. 2. Enable dual-mode sensing of heavy metals (Hg²⁺, Pb²⁺) and organics (pesticides, antibiotics) using SERS and electrochemical methods. 3. Assess pollutant removal through GSH’s chelation and Ag/Au NP-catalyzed reduction of organic pollutants. 4. Evaluate film reusability and stability in real water. #Hypothesis and Approach: We hypothesize that combining MXene, GSH, PEDOT:PSS, and Ag/Au NPs will yield a sensitive, multifunctional film. MXene offers conductivity, surface terminations, and area. Carboxylation (e.g., with citric acid) introduces -COOH groups, enhancing metal-ion affinity. GSH will be attached covalently via EDC coupling, exposing thiol and amine groups for metal and pollutant binding. The MXene-GSH complex, blended with PEDOT:PSS, forms a flexible, conductive film. Ag/Au NPs (added colloidally or in situ) generate plasmonic “hot spots” for SERS. This composite supports enhanced Raman and electrochemical signals (CV, DPV, EIS), enabling sub-ppb detection and pollutant degradation. #Main Experiments: Synthesis: Exfoliate MXene, carboxylate with citric acid, attach GSH via EDC/NHS. Confirm with XPS/FTIR. Film Fabrication: Blend MXene-GSH with PEDOT:PSS and Ag/Au NPs; cast films; analyze via SEM/TEM and conductivity. Application: SERS: Detect model pollutants; map enhancements. Electrochemistry: Detect Hg²⁺, Pb²⁺, antibiotics in spiked water. Remediation: Metal Uptake: Measure Hg²⁺ adsorption via ICP-MS/dithizone. Catalysis: e.g. Monitor NaBH₄-mediated 4-NP reduction via UV-vis. Field Testing: Validate in river/effluent samples; test reusability. #Significance and Impact: This is the first MXene-GSH/PEDOT:PSS plasmonic film for dual detection and remediation. It offers a low-cost, portable solution for real-time pollutant sensing and neutralization especially relevant to rural and resource-limited settings.