The current work describes the catalytic soot oxidation activity of metal‐doped manganese oxide (Mn1.9M0.1O3–δ; M = Co, Cu, and Ni) materials, synthesized by coprecipitation method. All the fabricated materials were characterized using X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller surface area analysis, and X‐ray photoelectron spectroscopy (XPS). XRD analysis confirmed the formation of solid solution Mn1.9M0.1O3–δ (M = Co, Cu, and Ni). M‐doped samples exhibited different morphology when compared with pure Mn2O3 as evidenced by FESEM analysis, and Co‐doped Mn2O3 possessed the highest specific surface area. XPS analysis revealed the presence of multiple oxidation states of Mn (+4, +3, and +2) and Co (+2 and +3). Soot oxidation activity tests, performed using thermogravimetric analysis, showed that Mn1.9Co0.1O3–δ exhibited better catalytic performance (T50 = 390°C) when compared with pure Mn2O3 (T50 = 490°C). The incorporation of dopants greatly enhanced the oxygen vacancies and redox properties of Mn2O3.

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Nanofibres of TiO 2 were synthesised by hydrothermal routine. Cellulose acetate/TiO 2 nanofibre composite membranes were synthesised via blending TiO 2 nanofibre in cellulose acetate solutions in 1-methyl-2-pyrrolidone. In order to study the effect of addition of nanofibre, membranes with various composition were synthesised, first by keeping cellulose acetate to 1-methyl-2pyrrolidone ratio constant and second by decreasing cellulose acetate concentration with increasing addition of TiO 2 nanofibre. The membranes were characterised using scanning electron microscope and X-ray diffraction. Hydrophilicity of the membranes was evaluated in terms of contact angle measurements and water uptake study. Permeation characteristics were determined in terms of pure water flux and bovine serum albumin rejection. Antifouling property was studied in terms of flux recovery after rejection. Remarkable improvement in membrane flux and antifouling properties is achieved by the addition of TiO 2 nanofibres.