Towards Visible Light Hydrogen Generation: Quantum Dot-Sensitization via Efficient Light Harvesting of Hybrid-TiO2
نویسندگان
چکیده
We report pronounced enhancement of photoelectrochemical hydrogen generation of a quantum dot-sensitized hybrid-TiO2 (QD/H-TiO2) electrode that is composed of a mesoporous TiO2 layer sandwiched by a double sided energy harvesting layer consisting of a surface-textured TiO2 inverse opals layer on the bottom and a patterned mesoporous TiO2 layer on the top. CdSe/H-TiO2 exhibits a maximum photocurrent density of ~16.2 mA/cm(2), which is 35% higher than that of the optimized control sample (CdSe/P25), achieved by matching of the bandgap of quantum dot-sensitization with the wavelength where light harvesting of H-TiO2 is observed. Furthermore, CdSe/H-TiO2 under filtered exposure conditions recorded current density of ~14.2 mA/cm(2), the greatest value in the visible range. The excellent performance of the quantum dot-sensitized H-TiO2 suggests that alteration of the photoelectrodes to suitable nanostructures with excellent light absorption may offer optimal strategies for attaining maximum efficiency in a variety of photoconversion systems.
منابع مشابه
S, N Co-Doped Graphene Quantum Dot/TiO2 Composites for Efficient Photocatalytic Hydrogen Generation
S, N co-doped graphene quantum dots (S,N-GQDs) coupled with P25 (TiO2) (S,N-GQD/P25) have been prepared via simply hydrothermal method. The as-prepared S,N-GQD/P25 composites exhibited excellent photocatalytic hydrogen generation activities, with a significantly extended light absorption range and superior durability without loading any noble metal cocatalyst. The photocatalytic activity of thi...
متن کامل339 FY 2008 Annual Progress Report DOE Hydrogen Program II
Investigation into integrated PEC/PVC for water splitting and light harvesting has focused on doping, QD sensitization and nanomaterials morphology. We have demonstrated, for the first time, PVC based on combined use of nitrogen doping and CdSe QD sensitization of nanocrystalline TiO2 thin films with promising results for solar energy conversion. Such TiO2:N/CdSe PVC produced an incident-photon...
متن کاملSILAR Sensitization as an Effective Method for Making Efficient Quantum Dot Sensitized Solar Cells
CdSe quantum dots were in situ deposited on various structures of TiO2 photoanode by successive ionic layer adsorption and reaction (SILAR). Various sensitized TiO2 structures were integrated as a photoanode in order to make quantum dot sensitized solar cells. High power conversion efficiency was obtained; 2.89 % (Voc=524 mV, Jsc=9.78 mA/cm2, FF=0.56) for the cells that sensitized by SILAR meth...
متن کاملHydrogen Generation Using Integrated Photovoltaic and Photoelectrochemical Cells
Investigation into integrated PEC/PVC for water splitting and light harvesting has focused on doping, QD sensitization and nanomaterials morphology. We have demonstrated, for the first time, PVC based on combined use of nitrogen doping and CdSe QD sensitization of nanocrystalline TiO2 thin films with promising results for solar energy conversion. Such TiO2:N/CdSe PVC produced an incident-photon...
متن کاملDye-sensitized Pt@TiO2 core–shell nanostructures for the efficient photocatalytic generation of hydrogen
Pt@TiO2 core-shell nanostructures were prepared through a hydrothermal method. The dye-sensitization of these Pt@TiO2 core-shell structures allows for a high photocatalytic activity for the generation of hydrogen from proton reduction under visible-light irradiation. When the dyes and TiO2 were co-excited through the combination of two irradiation beams with different wavelengths, a synergic ef...
متن کامل