The photocatalytic activity of Pac-Man particles is evaluated by the degradation of rhodamine B (RhB), a model organic dye for photocatalytic reactions. Prior to the photodegradation experiment, an aqueous solution of RhB (0.01 mM, 15 mL) is taken in a glass beaker together with Pac-Man microparticles (1 mg mL -1 ), which is then magnetically stirred in dark for 30 minutes to reach adsorption-desorption equilibrium of the dye on the catalyst surface. After the dark reaction, the solution is placed under a UV lamp (hand UV lamp from Herolab GmbH, Germany, lamp intensity 950 µW cm -2 and wavelength 365 nm) under magnetic stirring. The residual concentration (C) is noted after every 5 minutes for a 30 minutes time interval by measuring the absorbance intensity at its maximum absorbance wavelength of 553 nm. C 0 is the initial concentration and is taken at t = 0 mins (before irradiating with UV light). Measurements are taken in an absorbance range of 450 nm to 650 nm using a UV-visible spectrometer (Cary 60, Agilent Technologies) and in 1 cm path length quartz cuvette. A control sample is prepared in absence of the catalyst and measured under the same experimental conditions. The dye degradation efficiency (%) is determined as: