Phthalic Acid Esters (PAEs) are a well-known ubiquitous environmental pollutant that holds a significant threat to human health. Despite their harmful effects, the constant use of PAEs in producing flexible plastic products has awakened society's great concern, especially with their ability to leach, migrate, or evaporate from plastics to the surrounding. Therefore, rapid and easy monitoring of the PAEs presence in different environments is crucial. This study introduces a rapid PAE detection technique that shows potential for overcoming the limitations of already existing PAE detecting methods. This novel PAE sensing platform (buckypaper) is developed using highly conducting Multi-Walled Carbon Nanotubes (MWCNT).The buckypaper adsorbs PAEs in solutions and decreases its conductivity. This conductivity decrement is detected using the Nyquist and Bode plots obtain from three-electrode Electrochemical Impedance Spectroscopy (EIS) analysis. This novel method has shown that it has the potential to distinguish DEHP (di-(2-ethylhexyl) phthalate), DPHP (di-(2-propylheptyl) phthalate), and DnOP (di-octyl phthalate) from other aromatic molecules such as toluene, xylene, naphthalene, and bisphenol-A. Moreover, the developed buckypaper is sensitive down to 1000 (v/v) ppm concentrated PAEs in methanol solutions at room temperature, which exhibits the potential of using this platform as an in-situ and real-time PAE detecting sensor.

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Dye extracted from flesh of Clove fruit (Syzgium aromaticum) was used as the sensitizer in Dye Sensitized Solar Cells (DSSCs) of the configuration TiO2/dye/electrolyte/Pt. Pigments of Clove fruit was extracted by soaking in distilled water and ethanol and again boiling in both the solutions. Since DSSCs made using dye extraction in ethanol produced higher efficiency than in water, glacial acetic acid was added to dye extractions in ethanol at different ratios to examine any further enhancements. The Clove fruit extract absorbed appreciable solar radiation in the wavelength range 500 -700 nm that makes it suitable for a DSSC. FTIR spectra of the dye extracts revealed the hydroxyl groups attached to dye is prominent after acidification with acetic acid that helps to anchor on TiO2 surface. DSSC fabricated using mixture of fruit dye in ethanol and glacial acetic with the ratio of 1:3 produced the highest efficiency of 0.69 % with the photo current of 2.50 mAcm -2 and fill factor of 61.57 %. The electron life time calculated from bode phase plots of the cells also supported the above observations. The enhancement with acetic acid treatment of dye is attributed to intensification of absorption of visible light and strong coupling of the dye with TiO2 due to the presence of anchoring groups in acidic form is evidence from UV visible and FTIR spectroscopy.

Casein is the major protein present in cow's milk. Lowering the pH of cow's milk by addition of acids, natural casein can be precipitated, which can be utilized in fabricating thin film of polymer matrix for electrodes of optoelectronic devices. In the current study, casein was isolated by using several organic and inorganic acids. As organic acids, acetic, lactic, formic and ascorbic acids were used and H3PO4, H2SO4 and HNO3 were used as the inorganic acids.Thin films of casein were deposited on conducting tin oxide glass plates by using the casein precipitated with each acid and electrochemically characterized. But any significant difference could not be seen in the above measurements, where the same yield and results were obtained with all acids. Therefore, in further studies, casein isolated from acetic acid was used because of the safeness in using diluted acetic acid solution. These casein films were physically characterized by using impedance and optical spectroscopic techniques. Mott-Schottky analysis has shown that casein is having an n-type conductivity with flat band potential at -0.61V. The impedance spectroscopic analysis was used to calculate the electrical conductivity and dielectric constant of casein which were found to be 1.13×10 -2 mS/m and 6.6 respectively.The band gap of synthesized casein was determined by drawing tauc plot using the UV visible spectroscopic data which was found to be 3.9 eV. Fourier transform infrared spectra of casein sample were recoded to confirm the presence of functional groups in the synthesized compound. With this characterization, it was evident that casein is a prospective material to fabricate novel optoelectronic devices.