Similarly to alizarin molecules, 3,4-dihydroxy-9,10-dioxo-2-anthracenesulfonate (alizarin red, AR), chelates TiO2 nanoparticles through the catechol moiety, and shifts absorption threshold of semiconductor visible region. The photoinduced reactivity coupled system AR@TiO2 was investigated quantum yields determinations in nonscattering sols modified nanoparticles. In contrast with behavior observed microparticulated systems, chemisorbed ligand has a high stability under aerated light...

Electron accumulation in TiO2 ethanolic sols prepared by the HCl hydrolysis of a titanium alkoxide has been scrutinized UV–vis and EPR spectroscopy. Unexpectedly, Ti(III) centers, g = 1.9551, formed after controlled monochromatic irradiation could be detected at room temperature The yield paramagnetic signal number accumulated reducing species, dark titration experiments, increase as water to molar ratio, h, used synthesis diminishes. A 3.8% production efficiency was estimated for h 6.5....

A recent accomplishment in the preparation of a highly efficient thin film solar cell is reported. This superstrate composed FTO/TiO 2 /In S 3 /Cu ZnSnS 4 /graphite. maximum conversion efficiency 3.5% has been achieved for first time using this configuration and materials. The device includes low cost methods non‐toxic components. Details experimental procedures are provided characterization data presented analyzed. Left: Current–voltage response best /graphite dark (dotted line) under...

Photocurrent voltage curves obtained under visible light excitation of alizarin molecules chemisorbed to nanoporous TiO2 films show both anodic and cathodic currents. The potential at which the sign reversal occurs depends on electrolyte pH, presence acceptors, dye coverage, but as a general rule, it potentials ca. 600−700 mV more positive than flat band potential. Negative photocurrents are accounted by efficient electron discharge mediated ligand. Cathodic only observed pH values higher...

Reduction of alizarin molecules coupled to TiO(2) nanoparticles (A@TiO(2)) occurs on UV irradiation in the presence a sacrificial electron donor. Evidence is presented that reduction mediated by conduction-band electrons and yields 1,2,9,10-tetrahydroxyanthracene species which remains nanoparticles. The spectrum reduced complex displays two overlapping broad bands centred at 480 650 nm can harvest visible photons besides 900 nm, agreement with theoretical predictions TDDFT. potential...

Intensity modulated photovoltage and photocurrent spectroscopy data of CuInS₂ solar cells were modeled fitted with the solution continuity equation.

Herein we report the characterization and photoelectrochemical behavior of nanocrystalline TiO2 films modified with some alizarin derivatives. Particularly, complexone (3-[N,N-bis(carboxymethyl)-aminomethyl]-1,2-dihydroxyanthraquinone) its Fe(II) Fe(III) metal complexes have been examined. Based on UV-Visible Raman spectroscopic studies proposed that AC forms a tridentate complex titanium dioxide involving 2-OH (methylimino) diacetate groups, while AC-complexes bind to through carbonyl (CO)...

The enzymatic reduction of carbon dioxide presents limited applicability due to denaturation and the impossibility biocatalyst recovery; disadvantages that can be minimized by its immobilization. Here, a recyclable bio-composed system was constructed in-situ encapsulation under mild conditions using formate dehydrogenase in ZIF-8 metalorganic framework (MOF) presence magnetite. partial dissolution enzyme's operation medium relatively inhibited if concentration magnetic support used exceeds...

Solar cells are prepared combining ZnO as n‐type window In 2 S 3 buffer layer and CuInS p‐type absorbing layer. Superstrate configuration is chosen so that all the materials could be using inexpensive eco‐friendly techniques, based on solution processed deposition methods non‐toxic materials, avoiding vacuum high temperature Cd‐containing layers KCN purification stages. Also, no further sulfurization treatment involved in preparation. To improve collection efficiency, built two different...

TiO2 and CuInS2 (CIS) hetero-junctions were prepared using low-cost, solution-based techniques. Using conducting glass (FTO) as substrate, a thin film of an ultrathin In2S3 that acts buffer layer deposited by spray pyrolysis. CIS was electrodeposited on top this duplex layer, at pH 8, room temperature constant potential. A solar cell consisting FTO/TiO2/In2S3/CIS/graphite built in superstrate configuration. Morphology, thickness, crystalline structure chemical composition analyzed electronic...

Cu 2 ZnSnS 4 (CZTS) is a quaternary semiconductor that has emerged as potential absorber substitute for CuInGaSe in photovoltaic devices. This material excellent optical properties ( α ≥ 10 5 cm -1 ) and direct bandgap energy value E GAP close to 1.5 eV 1 . Furthermore, it does not contain toxic elements such selenium or expensive scarce ones indium gallium. Due these properties, CZTS films are being intensively studied candidates developing low-cost, highly efficient environmentally...

Cu 2 ZnSnS 4 (CZTS) is a kesterite-type material with promising properties among the materials suitable to be used as absorbers in solar cells. It highly absorbent ( α ≥ 10 5 cm -1 ), direct bandgap energy value E GAP ) for light absorption close 1.5 eV) [1]. The constituting elements are not toxic, expensive or scarce, case competing family compounds such chalcopyrites (CuInGaSe ). CZTS films thus excellent candidates low-cost, efficient and environmentally friendly cells [2]. There...