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Abstract: We have investigated the photoelectrochemical properties of hybrid films of polythiophenes poly(4,4″dimethoxy-3′-methyl-2,2′:5′,2″ terthiophene) (PDM), poly(4,4″dipentoxy-3′-methyl-2,2′:5′,2″ terthiophene) (PDP), and cadmium sulfide/zinc sulfide (CdS(ZnS)) core-shell nanoparticles. Although CdS(ZnS) nanoparticles present enhanced exciton trapping, light harvesting by hybrid films was enhanced when compared to those of pure PDM and PDP films. This enhancement is explained in terms of electron and hole transfer mechanisms at different excitation wavelengths. The more efficient light harvesting of PDM/CdS(ZnS) when compared to that of PDP/CdS(ZnS) was attributed to its broader absorption spectrum and more efficient electron hopping. [Copyright &y& Elsevier]

Abstract: This work reports on the photoelectrochemical properties of an interface comprised by poly(terthiophene) films electrochemically synthesized onto indium–tin oxide substrates and modified with 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61. Important photoelectrical parameters, such as flat band potential, density of charge carriers and depletion layer width were determined for the pristine and hybrid films. The cathodic photocurrent reflected the p-type semiconducting behavior of the electrosynthesized poly(terthiophene)s. Addition of the acceptor molecule improves the photocurrent at zero bias (∼6 μA cm−2 at 100 mW cm−2) indicating the fullerene derivative acts as an exciton dissociation center, improving the number of charge carriers transported through the polymer to reach the solid–liquid electrolyte interface. [Copyright &y& Elsevier]

Abstract In this work, we explore the impact of Zr precursor on the electrochemical and optical properties of V 2 O 5 thin films. These films were synthesized by the combination of the sol-gel route with dip-coating deposition on the electron conducting (fluorine tin oxide; FTO) substrate. We used vanadium oxytriisopropoxide (V) - [OV(OC 3 H 7) 3 ] and zirconium isopropoxide (IV) - [Zr(OCH 2 CH 2 CH 3) 4 ] as precursors, isopropanol as solvent, and glacial acetic acid as a catalyst. After the deposition, the thin films were subjected to densification at 350 °C for 30 min. We characterized these films by electrochemical techniques (cyclic voltammetry, chronoamperometry and chronocoulometry) and we obtained the best result of the load density of 109 mC·cm−2 for V 2 O 5 sample prepared with 5 mol% of Zr precursor; this sample also presented satisfactory responses of cyclic stability. We used atomic force microscopy (AFM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) to obtain morphology and crystallinity of this film. Its optical properties, we studied by UV–vis spectroscopy and the transmittance results were of 82% for the discolored and 39% for colored states, both measured at 633 nm. In summary, we show that V 2 O 5 :ZrO 2 thin films have quite attractive properties for their application as a working electrode in electrochromic devices. Graphical abstract Unlabelled Image Highlights • Different V 2 O 5 :ZrO 2 thin films were synthesized and characterized. • V 2 O 5 doped with 5 mol% ZrO 2 had the best value of charge density of 109 mC/cm2. • The ΔT between colored and discolored states of this film was 43% at 633 nm. • This film had an orthorhombic structure with the preferential (001) orientation in the crystalline plane. • The AFM topography evidenced dense and compact structure and RMS roughness of 7.06 nm. [ABSTRACT FROM AUTHOR]