Publications by Michael Graetzel

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Photoluminescence (PL) spectra of atomically thin 2D lead iodide perovskite films are shown to depend on excited-state density, especially at cryogenic temperatures. At high excited-state densities and low temperatures, free exciton (FE) emission is so sup ...

Recently, metal halide perovskite solar cells (PSCs) of the general formular ABX(3) where A is a monovalent cation, that is, methylammonium (MA) CH3NH3+center dot, formamidinium CH2(NH2)(2)(+), Cs+, or Rb+, B stands for Pb(II) or Sn(II), and X for iodide o ...

A process for catalytic oxidation of organic materials in waste water by hydrogen peroxide in the presence of iron (III) salts at temperatures below 80 DEG in the presence of titanium dioxide and with exposure to light.

A compound of formula (I): (X)nRuLL1 where n is 1 or 2, preferably 2, and in which Ru is ruthenium; each X independently is selected from Cl, SCN, H2O, Br, I, CN and SeCN and L is a ligand of formulae (a) to (g) and L1 is selected from a ligand of formulae (a) to (c) where each R independently is selected from OH, hydrogen, C1-20alkyl, -ORa or -N(Ra)2 and each Ra independently is hydrogen or C1-4alkyl.

Four new dye molecules comprising an anthanthrene core, thiophene-cyanoacrylic acid electron acceptor and triphenylamine (TPA) electron donor units were prepared. Thereby, the substitution pattern at the anthanthrene core has been varied systematically. Th ...

Cobalt-based electrolytes have significantly advanced the tunability and performance of dye-sensitized solar cells. The typically used platinum cathodes are expensive and non-optimal for cobalt complexes, motivating the search for replacements. Graphene na ...

Anodization of a-Fe2O3 (hematite) electrodes in alkaline electrolyte under constant potential conditions the electrode surface in a way that an additional current wave occurs in the cyclic voltammogram. The energy position of this current wave is closely b ...

Lack of proven stability has become a major obstacle on the path of metal halide perovskite solar cells (PSCs), in particular methylammonium lead triiodide (MAPbI(3)), towards commercial viability. This correlates with the intrinsic affinity of MAPbI(3) to ...

Due to the ease of tuning its redox potential, the cobalt-based redox couple has been extensively applied for highly efficient dye-sensitized solar cells (DSSCs) with extraordinarily high photovoltages. However, a cobalt electrolyte needs particular struct ...

Nanostructured Li4Ti5O12 (spinel) was prepared via a method employing lithium ethoxide and Ti(IV) alkoxides as the starting reagents. The optimized materials contained less than 1% of anatase as the main impurity and, depending on the synthetic conditions, they exhibited the BET surface areas of 5-183 m/g. Trace amount of anatase in Li4Ti5O12 was conveniently determined by cyclic voltammetry of Li-insertion. Thin-film electrodes from nanostructured Li4Ti5O12 spinel exhibit excellent activity towards Li-i

In this work we study in-depth the antireflection and filtering properties of ultrathin-metal-film-based transparent electrodes (MTEs) integrated in thin-film solar cells. Based on numerical optimization of the MTE design and the experimental characterizat ...

Despite well‐matching indoor illumination spectra, the performance of wide bandgap perovskite solar cells (WB‐PSCs) for indoor photovoltaics (i‐PV) is hindered by photo‐induced halide phase segregation and trap‐assisted non‐radiative recombination. Herein, ...

Two new photosensitizers featured with a cyanoacrylic acid electron acceptor (A) and a hybrid electron donor (D) of cyclopentadithiophene and dithiafulvenyl, either directly linked or separated by a phenyl ring, were synthesized and characterized. Both of ...

Novel optical sensing films for oxygen based on highly luminescent iridium (III) and ruthenium (II) complexes have been developed. These demonstrate excellent long-term photostability (several months) when incorporated into polystyrene membranes. The influ ...

We synthesized the Cu(II) and Zn(II) complexes of the 2,7,12,17-tetrapropionic acid of 3,8,13,18-tetramethyl-21H,23H porphyrin (coproporphyrin-I) and successfully employed them as sensitizers in dye-sensitized solar cells. Copper(II) coproporphyrin-I exhib ...

Thin-film photovoltaics play an important role in the quest for clean renewable energy. Recently, methylammonium lead halide perovskites were identified as promising absorbers for solar cells(1). In the three years since, the performance of perovskite-base ...

A photolytic system comprised of a darkened halfcell and an illuminated halfcell in which oxidation and reduction reactions are made to occur. These halfcells are joined by an electrically conductive element and an ion conducting junction for electron transfer and ion transport. The illuminated halfcell is equipped with a cathode and the darkened halfcell contains an improved anode which exhibits a desirably low overvoltage with respect to the substrate which is sought to be oxidized. Oxidation products are

Sunlight-driven CO2 reduction is a promising way to close the anthropogenic carbon cycle. Integrating light harvester and electrocatalyst functions into a single photo electrode, which converts solar energy and CO2 directly into reduced carbon species, is ...

Triazatruxene core based hole transporting materials (HTMs), HMDI (5,10,15-trihexyl-3,8,13-trimethoxy-10,15-dihydro-5H-diindolo[3,2-a: 3',2'-c]carbazole) and HPDI (5,10,15-tris(4-(hexyloxy)phenyl)-10,15-dihydro-5H-diindolo[3,2-a: 3',2'-c]carbazole) were sy ...

Perovskite solar cells have garnered significant interest, yet their limited operational stability remains a major challenge. This is especially pronounced at the interface with charge transport layers. In inverted p-i-n perovskite solar cells, fullerene-based electron transport layers pose critical stability issues. This has stimulated the application of low-dimensional perovskite interlayers featuring alkylammonium-based organic spacers that template perovskite slabs to enhance operational stabilities. Ho

Michael Graetzel

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How free exciton-exciton annihilation lets bound exciton emission dominate the photoluminescence of 2D-perovskites under high-fluence pulsed excitation at cryogenic temperatures

The Rise of Highly Efficient and Stable Perovskite Solar Cells

Catalytic oxidation of wastewater

Ruthenium complex dyes and photovoltaic cells utilizing them as photosensitizers

Anthanthrene dye-sensitized solar cells: influence of the number of anchoring groups and substitution motif

Carbon-graphene nanocomposite cathodes for improved Co(II/III) mediated dye-sensitized solar cells

Iron Resonant Photoemission Spectroscopy on Anodized Hematite Points to Electron Hole Doping during Anodization

Outdoor Performance and Stability under Elevated Temperatures and Long-Term Light Soaking of Triple-Layer Mesoporous Perovskite Photovoltaics

Molecular Engineering of Pyrido[3,4-b]pyrazine-Based Donor-Acceptor-pi- Acceptor Organic Sensitizers: Effect of Auxiliary Acceptor in Cobalt- and Iodine-Based Electrolytes

Process for producing Li4Ti5O12 and electrode materials

Infrared-reflective ultrathin-metal-film-based transparent electrode with ultralow optical loss for high efficiency in solar cells

Enhancing Indoor Photovoltaic Eﬃciency to 37.6% Through Triple Passivation Reassembly and n-Type to p-Type Modulation in Wide Bandgap Perovskites

A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells

Novel Oxygen Selective Complexes for Optical Oxygen Sensing

Application of Cu(II) and Zn(II) coproporphyrins as sensitizers for thin film dye sensitized solar cells

Perovskite solar cells employing organic charge-transport layers

Use of electrocatalytic anodes in photolysis

Covalent Immobilization of a Molecular Catalyst on Cu2O Photocathodes for CO2 Reduction

Rational design of triazatruxene-based hole conductors for perovskite solar cells

Electroactive naphthalimide and naphthalenediimide interlayers for inverted perovskite solar cells