Publications de Shaik Mohammed Zakeeruddin

Publications associées (514)

Sequential catalysis enables enhanced C-C coupling towards multi-carbon alkenes and alcohols in carbon dioxide reduction: a study on bifunctional Cu/Au electrocatalysts

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren, Jing Gao

Electrochemical reduction of carbon dioxide (CO2) to multi-carbon products such as ethylene, ethanol and n-propanol offers a promising path for utilization of excessive CO2 and energy storage. Oxide-derived Cu electrodes are among the best electrocatalysts ...

ROYAL SOC CHEMISTRY2019

Dynamic Nuclear Polarization Enables NMR of Surface Passivating Agents on Hybrid Perovskite Thin Films

Michael Graetzel, Shaik Mohammed Zakeeruddin, David Lyndon Emsley, Lukas Pfeifer, Aditya Mishra, Michael Allan Hope, Masaud Hassan S Almalki

Surface and bulk molecular modulators are the key to improving the efficiency and stability of hybrid perovskite solar cells. However, due to their low concentration, heterogeneous environments, and low sample mass, it remains challenging to characterize t ...

2022

Solution-based heteroepitaxial growth of stable mixed cation/anion hybrid perovskite thin film under ambient condition via a scalable crystal engineering approach

Michael Graetzel, Shaik Mohammed Zakeeruddin, Fabrizio Giordano

The performance of perovskite solar cells is under direct control of the perovskite film quality and controlling the crystalinity and orientation of solution-processed perovskite film is a fundamental challenge. In this study, we present a scalable fabrica ...

Elsevier2020

Suppressing recombination in perovskite solar cells via surface engineering of TiO2 ETL

Michael Graetzel, Shaik Mohammed Zakeeruddin, Daniel Prochowicz

Hybrid perovskite solar cells (PSCs) have gained significant attention owing to their excellent physicochemical and photovoltaic properties. PSCs typically consist of a perovskite light absorber sandwiched between two carrier selective layers optimized wit ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Hydroxamic acid pre-adsorption raises the efficiency of cosensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Nikolaos Vlachopoulos, Felix Thomas Eickemeyer, Yiming Cao, Jiajia Suo, Yameng Ren, Dan Zhang

Dye-sensitized solar cells (DSCs) convert light into electricity by using photosensitizers adsorbed on the surface of nanocrystalline mesoporous titanium dioxide (TiO2) films along with electrolytes or solid charge-transport materials(1-3). They possess ma ...

NATURE PORTFOLIO2023

Ti-1-graphene single-atom material for improved energy level alignment in perovskite solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Felix Thomas Eickemeyer, Zaiwei Wang, Hongwei Zhu

Carbon-based perovskite solar cells (C-PSCs) are widely accepted as stable, cost-effective photovoltaics. However, C-PSCs have been suffering from relatively low power conversion efficiencies (PCEs) due to severe electrode-related energy loss. Herein, we r ...

2021

Passivation of nanocrystalline TiO2 junctions by surface adsorbed phosphinate amphiphiles enhances the photovoltaic performance of dye sensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Mingkui Wang, Péter Kalman Péchy

We report a new class of molecular insulators that electronically passivate the surface of nanocrystalline titania films for high performance dye sensitized solar cells (DSC). Using electrical impedance measurements we demonstrate that co-adsorption of din ...

2009

Influence of the Donor Size in D-pi-A Organic Dyes for Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Shaik Mohammed Zakeeruddin, Pascal Comte, Thomas Moehl, Chenyi Yi, Joël Teuscher, Thomas Wesley Holcombe

We report two new molecularly engineered push-pull dyes, i.e., YA421 and YA422, based on substituted quinoxaline as a pi-conjugating linker and bulky-indoline moiety as donor and compared with reported IQ4 dye. Benefitting from increased steric hindrance w ...

American Chemical Society2014

Temperature-Dependent Ordering Phenomena of a Polyiodide System in a Redox-Active Ionic Liquid

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jacques-Edouard Moser, Jan Cornelius Brauer

Iodine added to iodide-based ionic liquids leads to dramatic changes of their physical properties which may have implications for technological applications. Here we study the phase diagram of 1-methyl 3-propylimidazolium iodide, the temperature versus iod ...

2012

New Insights into the Interface of Electrochemical Flow Cells for Carbon Dioxide Reduction to Ethylene

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren, Jing Gao

The implementation of an electrochemical flow cell has enabled improved efficiency for CO2 reduction. However, in situ spectroscopic insights into the interface are still lacking. Here, we investigate a series of copper layers with different thicknesses on ...

AMER CHEMICAL SOC2021

Super adsorption performance of carboxymethyl cellulose/copper oxide-nickel oxide nanocomposite toward the removal of organic and inorganic pollutants

Shaik Mohammed Zakeeruddin

A novel nanocomposite bead based on polymeric matrix of carboxymethyl cellulose and copper oxide-nickel oxide nanoparticles was synthesized, characterized, and applied for adsorptive removal of inorganic and organic contaminants at trace level of part per ...

SPRINGER HEIDELBERG2021

Electrochemical Properties of Cu(II/I)-Based Redox Mediators for Dye-Sensitized Solar Cells

Michael Graetzel, Ulf Anders Hagfeldt, Shaik Mohammed Zakeeruddin, Ladislav Kavan, Yasemin Saygili, Marina Freitag

Three Cu(II/I)-phenanthroline and Cu(II/I)-bipyridine redox mediators are studied on various electrodes and in variety of electrolyte solutions using cyclic voltammetry and impedance spectroscopy on symmetrical dummy cells. Graphene-based catalysts provide ...

2017

Significant Improvement of Dye-Sensitized Solar Cell Performance by Small Structural Modification in π-Conjugated Donor-Acceptor Dyes

Michael Graetzel, Shaik Mohammed Zakeeruddin, Robin Humphry-Baker, Jacques-Edouard Moser, Joël Teuscher, Magdalena Anna Marszalek, Mateusz Barnaba Wielopolski

Two donor-π-acceptor (D-π-A) dyes are synthesized for application in dye- sensitized solar cells (DSSC). These D-π-A sensitizers use triphenylamine as donor, oligothiophene as both donor and π-bridge, and benzothiadiazole (BTDA)/cyanoacrylic acid as accept ...

Wiley-Blackwell2012

Selective C-C Coupling in Carbon Dioxide Electroreduction via Efficient Spillover of Intermediates As Supported by Operando Raman Spectroscopy

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jingshan Luo, Dan Ren, Hong Zhang, Jing Gao

Developing efficient systems for the conversion of carbon dioxide to valuable chemicals using solar power is critical for mitigating climate change and ascertaining the worlds future supply of clean fuels. Here, we introduce a mesoscopic cathode consisting ...

AMER CHEMICAL SOC2019

New pyrido[3,4-b]pyrazine-based sensitizers for efficient and stable dye-sensitized solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jacques-Edouard Moser, Pascal Comte, Thomas Moehl, Mateusz Barnaba Wielopolski

A series of new pyrido[3,4-b]pyrazine-based organic sensitizers (PP-I and APP-I–IV) containing different donors and p-spacers have been synthesized and employed in dye-sensitized solar cells (DSSCs). The absorption spectra properties of dyes are analysed b ...

Royal Soc Chemistry2014

NiCuCoS3 chalcogenide as an efficient electrocatalyst for hydrogen and oxygen evolution

Michael Graetzel, Shaik Mohammed Zakeeruddin

Herein, a newly developed non-noble metal water splitting catalyst based on NiCuCoS3 was reported. Water splitting catalysts are largely developed with noble-based transition metals to lower the energy requirement for the overall water splitting reactions. ...

ELSEVIER2021

Solid-state synthesis of CdFe2O4 binary catalyst for potential application in renewable hydrogen fuel generation

Michael Graetzel, Shaik Mohammed Zakeeruddin

Clean energy is highly needed at this time when the energy requirements are rapidly increasing. The observed increasing energy requirement are largely due to continued industrialization and global population explosion. The current means of energy source is ...

Nature Portfolio2022

Ionic polarization-induced current–voltage hysteresis in CH3NH3PbX3 perovskite solar cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Peng Gao, Wolfgang Richard Tress, Thomas Moehl, Michael Saliba, Peng Gao, Yonghui Lee, Simone Meloni, Marius Franckevicius

CH3NH3PbX3 (MAPbX(3)) perovskites have attracted considerable attention as absorber materials for solar light harvesting, reaching solar to power conversion efficiencies above 20%. In spite of the rapid evolution of the efficiencies, the understanding of b ...

Nature Research2016

Spatial Conformation Engineering of Aromatic Ketones for Highly Efficient and Stable Perovskite Solar Cells

Minhuan Wang, Michael Graetzel, Shaik Mohammed Zakeeruddin, Likai Zheng, Xiaoqing Jiang

Carbonyl-containing materials employed in state-of-the-art hybrid lead halide perovskite solar cells (PSCs) exhibit a strong structure-dependent electron donor effect that predominates in defect passivation. However, the impact of the molecular spatial con ...

AMER CHEMICAL SOC2024

SnS Quantum Dots as Hole Transporter of Perovskite Solar Cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Peng Wang, Yuhang Liu, Dan Ren, Zaiwei Wang, Yang Li

Perovskite solar cells have achieved comparable power conversion efficiencies as commercial silicon cells, making the issue of long-term operation stability as the most critical scientific factor toward industrial realization. In this work, we introduce Sn ...

AMER CHEMICAL SOC2019