Structural changes of a globular protein, bovine serum albumin (BSA), as a consequence of interaction with the surface active ionic liquids (ILs)-3-methyl-1-octylimidazolium chloride, [C(8)mim][Cl], and 1-butyl-3-methylimidazolium octylsulfate, [C(4)mim][C(8)OSO(3)]-have been investigated using various physicochemical and spectroscopic techniques such as tensiometry, conductometry, steady-state fluorescence, far-UV circular dichroism spectroscopy (CD), and dynamic light scattering (DLS). The interactional behavior of ILs (monomers and self-assembled structures) toward BSA in different IL concentration regimes at the air/solution interface as well as in the bulk is investigated and discussed depending upon the nature of ions of ILs. CD combined with the steady state fluorescence spectroscopy provided valuable insights into the unfolding of BSA as a consequence of IL binding. The complementary results obtained from the multitechnique approach proved very useful in drawing out the mechanism of interaction between ILs and BSA in different IL concentration regimes.

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New graphene oxide (GO)-tethered-Co(II) phthalocyanine complex [CoPc-GO] was synthesized by a stepwise procedure and demonstrated to be an efficient, cost-effective and recyclable photocatalyst for the reduction of carbon dioxide to produce methanol as the main product. The developed GO-immobilized CoPc was characterized by X-ray diffraction (XRD), FTIR, XPS, Raman, diffusion reflection UV/Vis spectroscopy, inductively coupled plasma atomic emission spectroscopy (ICP-AES), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). FTIR, XPS, Raman, UV/Vis and ICP-AES along with elemental analysis data showed that Co(II) -Pc complex was successfully grafted on GO. The prepared catalyst was used for the photocatalytic reduction of carbon dioxide by using water as a solvent and triethylamine as the sacrificial donor. Methanol was obtained as the major reaction product along with the formation of minor amount of CO (0.82 %). It was found that GO-grafted CoPc exhibited higher photocatalytic activity than homogeneous CoPc, as well as GO, and showed good recoverability without significant leaching during the reaction. Quantitative determination of methanol was done by GC flame-ionization detector (FID), and verification of product was done by NMR spectroscopy. The yield of methanol after 48 h of reaction by using GO-CoPc catalyst in the presence of sacrificial donor triethylamine was found to be 3781.8881 μmol g(-1)  cat., and the conversion rate was found to be 78.7893 μmol g(-1) cat. h(-1). After the photoreduction experiment, the catalyst was easily recovered by filtration and reused for the subsequent recycling experiment without significant change in the catalytic efficiency.

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