scholarly journals Ultrafast Charge Transfer between Light Absorber and Co3O4 Water Oxidation Catalyst across Molecular Wires Embedded in Silica Membrane

2017 ◽  
Vol 139 (15) ◽  
pp. 5458-5466 ◽  
Author(s):  
Eran Edri ◽  
Jason K. Cooper ◽  
Ian D. Sharp ◽  
Dirk M. Guldi ◽  
Heinz Frei
Keyword(s):  
Charge Transfer ◽  
Water Oxidation ◽  
Molecular Wires ◽  
Oxidation Catalyst ◽  
Silica Membrane ◽  
Light Absorber ◽  
Ultrafast Charge Transfer

(Invited) Driving Metal Oxide Water Oxidation Catalyst By Visible Light Absorber Separated By an Ultrathin Proton Conducting Silica Membrane with Embedded Molecular Wires

2018 ◽  
Vol MA2018-01 (31) ◽  
pp. 1845-1845
Author(s):  
Heinz Frei
Keyword(s):  
Charge Transfer ◽  
Metal Oxide ◽  
Visible Light ◽  
Water Oxidation ◽  
Oxide Catalyst ◽  
Molecular Wires ◽  
Core Shell ◽  
Molecular Wire ◽  
Silica Membrane ◽  
Light Absorber

We are developing nanoscale photosynthetic assemblies for coupling the catalysis for CO2 reduction with the H2O oxidation half reaction, taking an inorganic molecular approach that utilizes heterobinuclear units such as ZrOCoII as light absorber coupled to metal oxide catalyst. Artificial nanoscale photosystems are inspired by natural photosynthesis, the only existing technology for producing energy-dense chemicals on the terawatt scale, which has as key design feature the closing of the cycle of water oxidation and formation of primary reduction intermediates on the shortest possible length scale, the nanometer scale, while separating the incompatible redox environments by an ultrathin membrane. To accomplish the photocatalytic cycle of CO2 reduction by H2O under membrane separation, we are exploring a Co oxide – silica core-shell nanotube geometry.1-3 The inside surface of the Co oxide nanotube core provides the catalytic sites for H2O oxidation, which are separated from light absorber and sites of CO2 reduction on the outside by an ultrathin (2 nm) dense phase silica layer. The latter functions as proton conducting, O2 impermeable membrane.4 Tight, molecular-level control of charge transfer between light absorber and Co oxide nanotube catalyst is accomplished by oligo-para(phenylene vinylene) molecules with 3 aryl units embedded in the silica shell.5 This approach addresses the requirements of robustness and tunability of the electronic properties of the photosystem components with the objective of converting the maximum fraction of the solar photon energy into chemical energy of the fuel.6 The core-shell nanotube geometry offers the opportunity of assembling macroscale arrays of enormous numbers of nanotubes, each operating as independent photosynthetic unit while at the same time providing separation of evolving O2 and reduced CO2 products on all length scales from nano to centimeters.3 Detailed characterization of charge transfer between light absorber and Co oxide catalyst across the silica membrane was investigated by transient optical absorption spectroscopy and photoelectro-chemical methods using nanotube, spherical, or planar morphology depending on the type of experiment. Ultrafast optical monitoring allowed us to detect transient positive charge (hole) on the silica embedded molecular wire and revealed very efficient, 255 ps transfer to the Co oxide catalyst.7 Short circuit current measurements upon visible light sensitized hole injection using sensitizers with different redox potentials showed that charge transfer is controlled by the HOMO and LUMO energetics of the silica embedded wire molecules.4,5 Synthetic methods were developed for the accurate selection of embedded molecular wire loading and tuning of the concentration. Electron transfer processes of visible light excited ZrOCo or TiOCo light absorbers coupled to silica embedded wires and Co oxide catalyst are being explored by transient optical spectroscopy and photoelectrochemical methods, and will be the main topic of the presentation.8 Time permitting, recent application of ultrathin silica membrane with embedded molecular wires for separating incompatible catalytic environments of electronically coupled inorganic and microbial components will also be discussed.9 [1] Kim, W.; Edri, E.; Frei, H. Acc. Chem. Res. 49, 1634 (2016) [2] Kim, W.; McClure, B. A.; Edri, E.; Frei, H. Chem. Soc. Rev. 45, 3221 (2016) [3] Edri, E.; Aloni, S.; Frei, H., ACS Nano, submitted [4] Yuan, G.; Agiral, A.; Pellet, N.; Kim, W.; Frei, H. Faraday Discuss. 176, 233 (2014) [5] Edri, E.; Frei, H. J. Phys. Chem. C 119, 28326 (2015) [6] Frei, H. Curr. Opin. Electrochem. 2, 128 (2017) [7] Edri, E.; Cooper, J. K.; Sharp, I. D.; Guldi, D. M.; Frei, H. J. Am. Chem. Soc. 139, 5458 (2017) [8] Katsoukis, G.; Frei, H., to be submitted [9] Cornejo, J. A.; Sheng, H.; Edri, E.; Ajo-Franklin, C.; Frei, H., submitted

Visible Light Induced Hole Transport from Sensitizer to Co3O4 Water Oxidation Catalyst across Nanoscale Silica Barrier with Embedded Molecular Wires

2013 ◽  
Vol 25 (11) ◽  
pp. 2264-2273 ◽  
Author(s):  
Anil Agiral ◽  
Han Sen Soo ◽  
Heinz Frei
Keyword(s):  
Visible Light ◽  
Water Oxidation ◽  
Molecular Wires ◽  
Hole Transport ◽  
Oxidation Catalyst

scholarly journals A stable dye-sensitized photoelectrosynthesis cell mediated by a NiO overlayer for water oxidation

2019 ◽  
Vol 117 (23) ◽  
pp. 12564-12571 ◽  
Author(s):  
Degao Wang ◽  
Fujun Niu ◽  
Michael J. Mortelliti ◽  
Matthew V. Sheridan ◽  
Benjamin D. Sherman ◽  
...  
Keyword(s):  
Water Oxidation ◽  
Photocurrent Density ◽  
Oxidation Catalysis ◽  
Oxidation Catalyst ◽  
Photoelectrochemical Cells ◽  
Half Cell ◽  
Dye Sensitized ◽  
Light Absorber ◽  
Water Oxidation Catalysis

In the development of photoelectrochemical cells for water splitting or CO2reduction, a major challenge is O2evolution at photoelectrodes that, in behavior, mimic photosystem II. At an appropriate semiconductor electrode, a water oxidation catalyst must be integrated with a visible light absorber in a stable half-cell configuration. Here, we describe an electrode consisting of a light absorber, an intermediate electron donor layer, and a water oxidation catalyst for sustained light driven water oxidation catalysis. In assembling the electrode on nanoparticle SnO2/TiO2electrodes, a Ru(II) polypyridyl complex was used as the light absorber, NiO was deposited as an overlayer, and a Ru(II) 2,2′-bipyridine-6,6′-dicarboxylate complex as the water oxidation catalyst. In the final electrode, addition of the NiO overlayer enhanced performance toward water oxidation with the final electrode operating with a 1.1 mA/cm2photocurrent density for 2 h without decomposition under one sun illumination in a pH 4.65 solution. We attribute the enhanced performance to the role of NiO as an electron transfer mediator between the light absorber and the catalyst.

Boosted charge transfer in oxygen vacancy-rich K+ birnessite MnO2 for water oxidation and zinc-ion batteries

2021 ◽  
Vol 378 ◽  
pp. 138147
Author(s):  
MengXian Lin ◽  
Fuqiang Shao ◽  
Shuting Weng ◽  
Shanshan Xiong ◽  
Shuai Liu ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Oxygen Vacancy ◽  
Water Oxidation ◽  
Zinc Ion

Ultrafast charge transfer at the electrode−electrolyte interface via an artificial dielectric layer

2021 ◽  
Vol 494 ◽  
pp. 229710
Author(s):  
Takashi Teranishi ◽  
Kaisei Kozai ◽  
Sou Yasuhara ◽  
Shintaro Yasui ◽  
Naoyuki Ishida ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Dielectric Layer ◽  
Electrolyte Interface ◽  
Artificial Dielectric ◽  
Ultrafast Charge Transfer

Ultrafast Charge Transfer and Relaxation at a Donor–Acceptor Interface

2021 ◽  
Author(s):  
Fernando Rodríguez Díaz ◽  
Hong-Guang Duan ◽  
R. J. Dwayne Miller ◽  
Michael Thorwart
Keyword(s):  
Charge Transfer ◽  
Donor Acceptor ◽  
Ultrafast Charge Transfer

Fast microwave-assisted preparation of nickel–copper–chromium-layered double hydroxide as an excellent electrocatalyst for water oxidation

2021 ◽  
Author(s):  
Kamellia Nejati ◽  
Leila Jafari Foruzin ◽  
Zolfaghar Rezvani
Keyword(s):  
Charge Transfer ◽  
Layered Double Hydroxide ◽  
Water Oxidation ◽  
Bandgap Energy ◽  
Microwave Method ◽  
Optimal Amount ◽  
Microwave Assisted ◽  
Nickel Copper ◽  
Copper Chromium ◽  
Double Hydroxide

A well-designed NiCuCr-LDH was prepared using a simple microwave method. According to the OER results, doping optimal amount of Cu2+ into NiCr-LDH displayed superior OER activity, due to decreased bandgap energy and improved charge transfer.

Conductive Polymer Intercalation Tunes Charge Transfer and Sorption–Desorption Properties of LDH Enabling Efficient Alkaline Water Oxidation

2021 ◽  
Author(s):  
Min Ju ◽  
Rongming Cai ◽  
Jiazheng Ren ◽  
Jinxi Chen ◽  
Limin Qi ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Water Oxidation ◽  
Conductive Polymer ◽  
Alkaline Water
Sign in / Sign up

Export Citation Format

Share Document