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For a reliable and risk-free power source, dye-sensitized solar cells (DSSCs) have been the subject of much research. The method is very attractive because of its cheap manufacturing cost, environmentally friendly manufacture, and competitive efficiency. This study constructed a heterojunction as a photoanode for DSSCs using a combination of TiO2 and graphene using a wet chemical technique. According to the XRD and TEM findings, the graphene sheets consist of evenly wrapped spherical nanoparticles with diameters ranging from 30 to 40 nm, and the TiO2 exhibits a tetragonal (anatase) phase. It is common for anatase to have a bandgap energy of 3.15 eV for TiO2, whereas graphene/TiO2 has a bandgap energy of 2.77 eV. With a power conversion efficiency (PCE) of 7.2%, graphene/TiO2 DSSCs outperform cells based on pure TiO2 electrodes by a margin of 2.22%. In particular, graphene's ability to absorb solar light has the potential to improve the power conversion efficiency of DSSCs by increasing the light harvest of dye molecules. In addition, graphene/TiO2 had an average electron transit time of 1.765 ms while TiO2 had an average of 2.981 ms. The research shows that DSSCs' power conversion efficiency may be greatly improved by strategically adding graphene, which can be affordably synthesized, to certain layers of the photoanode. [ABSTRACT FROM AUTHOR]

The present study is aimed at developing a sensitive biosensor for urea by the incorporation of MWCNT- Inulin-TiO 2 and urease (Ur) onto carbon paste matrix and to propose a suitable mechanism of interaction. Multi-Walled Carbon nanotubes (MWCNTs) were considered as a novel nanomaterial owing to their unique properties but their hydrophobicity limit their applications. A successful strategy to improve their hydrophilicity is to modify MWCNTs with biopolymers. Inulin (Inu), a versatile carbohydrate polymer was extracted from Allium sativum L. and used for anchoring TiO 2 . The prepared Inu-TiO 2 composite was used to modify MWCNTs in order to synergistically improve the stability and the biocompatibility. The MWCNT-Inu-TiO 2 bio-nanocomposite was characterized by UV–vis, FT-IR, micro-Raman, XRD, SEM, TEM and TGA techniques. Differential Pulse Voltammetric (DPV) studies were carried out to show the sensitivity of the fabricated CP/MWCNT-Inu-TiO 2 /Ur bioelectrode towards urea. The fabricated bioelectrode exhibited wide linear range (0.083 mM to 25 mM) with low detection limit (0.9 μM), good sensitivity (29.6 mA mM −1  cm -2 ), high storage stability (120 days) and good selectivity (in presence of biointerferences like ascorbic acid, uric acid, glucose, lactose, Na + and K + ). The fabricated bioelectrode was also effectively applied for the sensing of urea as an adulterant in milk samples. [ABSTRACT FROM AUTHOR]

• Sensing trace level of glucose in commercial food products is important. • CP/MWCNT-Inulin-TiO 2 /GOx, a new kind of electrode was fabricated for sensing glucose. • Nanomolar sensing of glucose in sugar free products was achieved using the electrode. • Study revealed that some of the sugar free products were not 100% glucose free. • Storage stability (150 days) was higher than that of other carbon based electrodes. Development of an effective sensor for sensing glucose in commercially available "sugar free" food products is important as people are becoming diabetic health conscious. Although multi-walled carbon nanotubes (MWCNTs) possess interesting electrical properties, their hydrophobic nature limits their applications. Their hydrophilicity can be improved through modification. In the present study, Inulin, that was isolated from Allium sativum L. using hot water diffusion and incorporated with titanium dioxide (TiO 2), was used for the modification of MWCNTs. The as-synthesized MWCNT-Inulin-TiO 2 bio-nanocomposite immobilized with glucose oxidase (GOx) was incorporated into the carbon paste matrix and was utilized for the sensing of glucose in food products. Differential pulse voltammetric studies revealed that the fabricated electrode demonstrated good linear range (1.6 nM to 1 μM) and was sensitive to nanomolar concentrations of glucose with a very low limit of detection up to 0.82 nM and exhibited a long term stability of 150 days. [ABSTRACT FROM AUTHOR]