The Experts below are selected from a list of 6447 Experts worldwide ranked by ideXlab platform

Licheng Sun - One of the best experts on this subject based on the ideXlab platform.

  • visible light driven selective oxidation of benzyl alcohol and thioanisole by molecular ruthenium catalyst modified hematite
    Chemical Communications, 2016
    Co-Authors: Lichen Bai, Licheng Sun, Yong Wang, Xiaojuan Jiang
    Abstract:

    Molecular ruthenium catalysts were found to selectively catalyze the oxidation of thioanisole to sulfoxide with a yield up to 100% in the presence of visible light and sacrificial reagents when they were anchored onto hematite powder. The composite photocatalysts also showed about 5 times higher efficiencies in benzyl alcohol oxidation than the system composed of dispersed molecular catalysts and hematite particles in aqueous solution. A Photoelectrochemical Cell based on a molecular catalyst modified hematite photoanode was further fabricated, which exhibited high activity towards the oxidation of organic substrates.

  • organic dye sensitized tandem Photoelectrochemical Cell for light driven total water splitting
    Journal of the American Chemical Society, 2015
    Co-Authors: Ke Fan, Erik Gabrielsson, Quentin Daniel, Licheng Sun
    Abstract:

    Light driven water splitting was achieved by a tandem dye-sensitized Photoelectrochemical Cell with two photoactive electrodes. The photoanode is constituted by an organic dye L0 as photosensitizer and a molecular complex Ru1 as water oxidation catalyst on meso-porous TiO2, while the photocathode is constructed with an organic dye P1 as photoabsorber and a molecular complex Co1 as hydrogen generation catalyst on nanostructured NiO. By combining the photocathode and the photoanode, this tandem DS-PEC Cell can split water by visible light under neutral pH conditions without applying any bias.

  • visible light driven water splitting in a molecular device with unprecedentedly high photocurrent density
    Journal of the American Chemical Society, 2013
    Co-Authors: Yan Gao, Xin Ding, Jianhui Liu, Lei Wang, Licheng Sun
    Abstract:

    A molecular water oxidation catalyst (2) has been synthesized and immobilized together with a molecular photosensitizer (1) on nanostructured TiO2 particles on FTO conducting glass, forming a photoactive anode (TiO2(1+2)). By using the TiO2(1+2) as working electrode in a three-electrode Photoelectrochemical Cell (PEC), visible light driven water splitting has been successfully demonstrated in a phosphate buffer solution (pH 6.8), with oxygen and hydrogen bubbles evolved respectively from the working electrode and counter electrode. By applying 0.2 V external bias vs NHE, a high photocurrent density of more than 1.7 mA·cm–2 has been achieved. This value is higher than any PEC devices with molecular components reported in literature.

Jong-hyeok Park - One of the best experts on this subject based on the ideXlab platform.

  • Photoelectrochemical Cell dye sensitized solar Cell tandem water splitting systems with transparent and vertically aligned quantum dot sensitized tio2 nanorod arrays
    Journal of Power Sources, 2013
    Co-Authors: Kahee Shin, Jibeom Yoo, Jong-hyeok Park
    Abstract:

    Abstract The present work reports fabrication of vertically aligned CdS sensitized TiO 2 nanorod arrays grown on transparent conducting oxide substrate with high transparency as a photoanode in Photoelectrochemical Cell for water splitting. To realize an unassisted water splitting system, the photoanode and dye-sensitized solar Cell tandem structures are tried and their electrochemical behaviors are also investigated. The hydrothermally grown TiO 2 nanorod arrays followed by CdS nanoparticle decoration can improve the light absorption of long wavelength light resulting in increased photocurrent density. Two different techniques (electrodeposition and spray pyrolysis deposition) of CdS nanoparticle sensitization are carried out and their water splitting behaviors in the tandem Cell are compared.

  • Synthesis and Photoelectrochemical Cell properties of vertically grown α-Fe2O3 nanorod arrays on a gold nanorod substrate
    Journal of Materials Chemistry, 2010
    Co-Authors: Aiming Mao, Gui Young Han, Jong-hyeok Park
    Abstract:

    Photoelectrochemical Cells prepared from highly ordered and vertically grown alpha-Fe2O3 nanorod arrays on a Au nanorod substrate showed about 8 mA cm(-2) photocurrent density under 1 sun condition without any hole scavenger. To the best of our knowledge, it is the highest value obtained from alpha-Fe2O3. The Au nanorod arrays were firstly grown inside the AAO nanotubes to provide a conductive surface, not only for the electrochemical deposition of the target material, but also to act as the current collector of a Photoelectrochemical Cell. Then, the Fe nanorods were electrodeposited on the gold nanorods and annealed in an O-2 atmosphere to convert them into alpha-Fe2O3 nanorod arrays. The alpha-Fe2O3 nanorod arrays stood freely on the gold nanorod arrays after the removal of the AAO template. The Photoelectrochemical properties of the alpha-Fe2O3 nanorod arrays as a photoanode were studied by evaluating their photocurrent-potential behavior in 1 M NaOH electrolyte under AM 1.5 100 mW cm(-2) illumination. Also, the dependence of the photocatalytic ability of the alpha-Fe2O3 nanorod arrays on their length was studied and the optimum rod length was determined.

  • Photoelectrochemical Tandem Cell with Bipolar Dye-Sensitized Electrodes for Vectorial Electron Transfer for Water Splitting
    Electrochemical and Solid-State Letters, 2006
    Co-Authors: Jong-hyeok Park, Allen J. Bard
    Abstract:

    Direct water electrolysis was achieved with a novel monolithic Photoelectrochemical Cell. Bipolar WO 3 /Pt and dye-sensitized TiO 2 /Pt semiconductor panels, capable of vectorial electron transfer, have been used for water splitting to yield hydrogen and oxygen; light is the only energy input. The hydrogen production efficiency of this tandem Cell, based on the short-circuit current, was ∼1.9% and the maximum hydrogen production efficiency was ∼2.5% when 0.2 V positive bias was applied. When a concentrated LiCI aqueous solution was used as an electrolyte, valuable chlorine was obtained instead of oxygen. The maximum yielding efficiency of hydrogen and chlorine was ∼1.8%.

Jian Chen - One of the best experts on this subject based on the ideXlab platform.

  • integrating a dual silicon Photoelectrochemical Cell into a redox flow battery for unassisted photocharging
    Nature Communications, 2016
    Co-Authors: Shichao Liao, Chunmei Ding, Xu Zong, Brian Seger, Thomas Pedersen, Jian Chen, Can Li
    Abstract:

    Technologies for in situ capture and storage of intermittent solar energy are an important research goal. Here the authors report a solar rechargeable flow Cell based on a dual-silicon Photoelectrochemical Cell and a quinone/bromine redox flow battery for in situ solar energy conversion and storage.

  • integrating a dual silicon Photoelectrochemical Cell into a redox flow battery for unassisted photocharging
    Nature Communications, 2016
    Co-Authors: Shichao Liao, Chunmei Ding, Xu Zong, Brian Seger, Thomas Pedersen, Tingting Yao, Jingying Shi, Jian Chen
    Abstract:

    Solar rechargeable flow Cells (SRFCs) provide an attractive approach for in situ capture and storage of intermittent solar energy via Photoelectrochemical regeneration of discharged redox species for electricity generation. However, overall SFRC performance is restricted by inefficient Photoelectrochemical reactions. Here we report an efficient SRFC based on a dual-silicon Photoelectrochemical Cell and a quinone/bromine redox flow battery for in situ solar energy conversion and storage. Using narrow bandgap silicon for efficient photon collection and fast redox couples for rapid interface charge injection, our device shows an optimal solar-to-chemical conversion efficiency of ∼5.9% and an overall photon-chemical-electricity energy conversion efficiency of ∼3.2%, which, to our knowledge, outperforms previously reported SRFCs. The proposed SRFC can be self-photocharged to 0.8 V and delivers a discharge capacity of 730 mAh l(-1). Our work may guide future designs for highly efficient solar rechargeable devices.

Xu Zong - One of the best experts on this subject based on the ideXlab platform.

  • integrating a dual silicon Photoelectrochemical Cell into a redox flow battery for unassisted photocharging
    Nature Communications, 2016
    Co-Authors: Shichao Liao, Chunmei Ding, Xu Zong, Brian Seger, Thomas Pedersen, Jian Chen, Can Li
    Abstract:

    Technologies for in situ capture and storage of intermittent solar energy are an important research goal. Here the authors report a solar rechargeable flow Cell based on a dual-silicon Photoelectrochemical Cell and a quinone/bromine redox flow battery for in situ solar energy conversion and storage.

  • integrating a dual silicon Photoelectrochemical Cell into a redox flow battery for unassisted photocharging
    Nature Communications, 2016
    Co-Authors: Shichao Liao, Chunmei Ding, Xu Zong, Brian Seger, Thomas Pedersen, Tingting Yao, Jingying Shi, Jian Chen
    Abstract:

    Solar rechargeable flow Cells (SRFCs) provide an attractive approach for in situ capture and storage of intermittent solar energy via Photoelectrochemical regeneration of discharged redox species for electricity generation. However, overall SFRC performance is restricted by inefficient Photoelectrochemical reactions. Here we report an efficient SRFC based on a dual-silicon Photoelectrochemical Cell and a quinone/bromine redox flow battery for in situ solar energy conversion and storage. Using narrow bandgap silicon for efficient photon collection and fast redox couples for rapid interface charge injection, our device shows an optimal solar-to-chemical conversion efficiency of ∼5.9% and an overall photon-chemical-electricity energy conversion efficiency of ∼3.2%, which, to our knowledge, outperforms previously reported SRFCs. The proposed SRFC can be self-photocharged to 0.8 V and delivers a discharge capacity of 730 mAh l(-1). Our work may guide future designs for highly efficient solar rechargeable devices.

  • selective production of hydrogen peroxide and oxidation of hydrogen sulfide in an unbiased solar Photoelectrochemical Cell
    Energy and Environmental Science, 2014
    Co-Authors: Xu Zong, Brian Seger, Hongjun Chen, Thomas Garm Pedersen, Matthew S Dargusch, Eric W Mcfarland, Lianzhou Wang
    Abstract:

    A solar-to-chemical conversion process is demonstrated using a Photoelectrochemical Cell without external bias for selective oxidation of hydrogen sulfide (H2S) to produce hydrogen peroxide (H2O2) and sulfur (S). The process integrates two redox couples anthraquinone/anthrahydroquinone and I−/I3−, and conceptually illustrates the remediation of a waste product for producing valuable chemicals.

Prashant V Kamat - One of the best experts on this subject based on the ideXlab platform.

  • photosensitization of tio2 nanostructures with cds quantum dots particulate versus tubular support architectures
    Advanced Functional Materials, 2009
    Co-Authors: David R Baker, Prashant V Kamat
    Abstract:

    TiO2 nanotube arrays and particulate films are modified with CdS quantum dots with an aim to tune the response of the Photoelectrochemical Cell in the visible region. The method of successive ionic layer adsorption and reaction facilitates size control of CdS quantum dots. These CdS nanocrystals, upon excitation with visible light, inject electrons into the TiO2 nanotubes and particles and thus enable their use as photosensitive electrodes. Maximum incident photon to charge carrier efficiency (IPCE) values of 55% and 26% are observed for CdS sensitized TiO2 nanotube and nanoparticulate architectures respectively. The nearly doubling of IPCE observed with the TiO2 nanotube architecture is attributed to the increased efficiency of charge separation and transport of electrons.

  • single wall carbon nanotube scaffolds for Photoelectrochemical solar Cells capture and transport of photogenerated electrons
    Nano Letters, 2007
    Co-Authors: Anusorn Kongkanand, Rebeca Martinez Dominguez, Prashant V Kamat
    Abstract:

    Single wall carbon nanotube (SWCNT) architecture when employed as conducting scaffolds in a TiO2 semiconductor based Photoelectrochemical Cell can boost the photoconversion efficiency by a factor of 2. Titanium dioxide nanoparticles were dispersed on SWCNT films to improve photoinduced charge separation and transport of carriers to the collecting electrode surface. The shift of ∼100 mV in apparent Fermi level of the SWCNT−TiO2 system as compared to the unsupported TiO2 system indicates the Fermi level equilibration between the two systems. The interplay between the TiO2 and SWCNT of attaining charge equilibration is an important factor for improving Photoelectrochemical performance of nanostructured semiconductor based solar Cells. The feasibility of employing a SWCNT−TiO2 composite to drive the water photoelectrolysis reaction has also been explored.