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Cerium-doped MoO3 thin films were grown through spray pyrolysis using (NH4) 6Mo7O 24 4H2O 0.1 M solution. The doping was performed by adding 0.1M CeCl3.7H2O, in a ratio of 2% by volume. X-ray and Auger electron spectra show of Ce incorporation in MoO3 thin film. X-ray diffraction showed that Cerium insertion destroys the α-MoO3 structure observed in undoped films. The electrochemical properties were studied using the cyclic voltammetry technique with -400 to 400 mV and scanning speeds from 16 to 144 mV/s. It was established that the diffusion coefficient varies from 1.06 x 10-10 cm²/s for the undoped film to 3.49 x 10 cm²/s for doped film. This suggests that the doped film favors ion exchange processes. The optical transmittance in the range of 290-2500 nm showed that the light transmission of the film doped with Cerium is higher by 10% compared to the undoped film. [ABSTRACT FROM AUTHOR]

• The hexagonal and monoclinic structures of plantain starches were altered by chemical modification. • The peak viscosity of OSA-starches (DH and FHIA 21) decreased compared to native counterpart. • The amylose content increased after the modification for DH and FHIA starches. • FHIA 21 starch was greater modified than DH starch. Chemical modification with octenyl succinic anhydride (OSA) helps to control the physicochemical and thermal properties of isolated starches. The main objective, herein, was to partially characterize modified starches from Dominico-Harton plantain and FHIA 21 planted in Colombia. The highest degree of substitution was found in FHIA 21 (0.020) starch with 3% OSA and 4-h reaction at room temperature. The grain morphology was not affected, but small changes on the surface were evident. Both modified starches reported absorption bands in the IR at 1566 and 1738 cm−1, proper for these types of starch derivatives. The hexagonal and monoclinic structures of starch were altered through chemical modification. In the bending curves, a drastic decrease in the viscosity of the modified starches was observed with respect to the native one. The gelatinization temperatures of the modified starches were similar to those of the isolated starches. [ABSTRACT FROM AUTHOR]