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Iwan Zimmermann

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Related publications (39)

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Investigation of the Structural and Electrochemical Properties of Mn2Sb3O6CI upon Reaction with Li Ions

Iwan Zimmermann

The structural and electrochemical properties of a quaternary layered compound with elemental composition Mn2Sb3O6Cl have been investigated upon reaction with lithium in Li half cells. Operando XRD was used to investigate the potential impact of this parti ...

Amer Chemical Soc2017

Effect of annealing temperature on the performance of printable carbon electrodes for perovskite solar cells

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

Perovskite solar cells (PSCs) with mesoporous TiO2 electron transport layers have reached > 22% efficiency at laboratory scale ( < 1 cm(2)), however, these layers are fabricated using spin-coating, which is not conducive to large-scale or high throughput f ...

ELSEVIER SCIENCE BV2019

Hole transporting materials for perovskite solar cells and a simple approach for determining the performance limiting factors

Mohammad Khaja Nazeeruddin, Tom Theodorus Antonius Lummen, Iwan Zimmermann

The synthesis and characterization of three novel HTMs with different highest occupied molecular orbital (HOMO) energy levels and their performances in MAPbI(3)-based devices in comparison with Spiro-OMeTAD is reported. Without systematic optimization, the ...

Royal Society of Chemistry2020

Tapered Cross-Section Photoelectron Spectroscopy of State-of-the-Art Mixed Ion Perovskite Solar Cells: Band Bending Profile in the Dark, Photopotential Profile Under Open Circuit Illumination, and Band Diagram

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

The purpose of this article is twofold. On the one hand the method of spacial resolved photoemission spectroscopy on small angle tapered cross-sections (TCS) of complete devices is introduced to analyze simultaneously the chemical and electronic structure. ...

WILEY-V C H VERLAG GMBH2020

CuSCN as Hole Transport Material with 3D/2D Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

We report stable perovskite solar cells having 3D/2D perovskite absorber layers and CuSCN as an inorganic hole transporting material (HTM). (Phenylethyl)ammonium (PEA) and [(4-fluorophenyl)ethyl]ammonium (FPEA) have been chosen as 2D cations, creating thin ...

AMER CHEMICAL SOC2020

Hole-Transporting Materials for Perovskite Solar Cells Employing an Anthradithiophene Core

Mohammad Khaja Nazeeruddin, Hiroyuki Kanda, Iwan Zimmermann, Inés Garcia Benito

A decade after the report of the first efficient perovskite-based solar cell, development of novel hole-transporting materials (HTMs) is still one of the main topics in this research field. Two of the main advance vectors of this topic lie in obtaining mat ...

AMER CHEMICAL SOC2021

Charge Extraction and Recombination Dynamics of CdSe/CdTe Solar Cells Studied with Transient Photovoltage/Photocurrent Techniques

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

Significant advancements have been made in the development of high-performance cadmium telluride (CdTe)-based thin film solar cells. However, studies examining the transient excited-state charge dynamics, which determine the final steady-state device perfo ...

IEEE2023

Surface, Interface, and Bulk Electronic and Chemical Properties of Complete Perovskite Solar Cells: Tapered Cross-Section Photoelectron Spectroscopy, a Novel Solution

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

The surface, interface, and bulk properties are a few of the most critical factors that influence the performance of perovskite solar cells. The photoelectron spectroscopy (PES) is used as a technique to analyze these properties. However, the information d ...

AMER CHEMICAL SOC2020

A Facile Preparative Route of Nanoscale Perovskites over Mesoporous Metal Oxide Films and Their Applications to Photosensitizers and Light Emitters

Mohammad Khaja Nazeeruddin, Emad Oveisi, Giulia Grancini, Sanghyun Paek, Kyung Taek Cho, Iwan Zimmermann, Yonghui Lee, Aron Joel Huckaba, Valentin Ianis Emmanuel Queloz, So-Min Yoo

By two‐step sequential Pb2+ adsorption and reaction with methylammonium‐iodide (MAI) or ‐bromide (MABr) at a low concentration level of 0.06–0.10 m over mesoporous TiO2 or ZrO2 film, a well‐defined nanoscale CH3NH3PbI3 (MAPbI3) photosensitizer or CH3NH3PbB ...

2018

Copper Thiocyanate Inorganic Hole-Transporting Material for High-Efficiency Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Giulia Grancini, Cristina Roldán Carmona

In this Letter we show that the mixed perovskite in the form of (FAPbI(3))(0.85)(MAPbBr(3))(0.15) in combination with CuNCS as p-type hole conductor leads to over 16% power conversion efficiency (PCE) under full sun illumination and yields a remarkable mon ...

Amer Chemical Soc2016

Lead and HTM Free Stable Two-Dimensional Tin Perovskites with Suitable Band Gap for Solar Cell Applications

Mohammad Khaja Nazeeruddin, Tom Theodorus Antonius Lummen, Iwan Zimmermann, Sadig Aghazada

Organic-inorganic hybrid perovskites have attracted great attention over the last few years as potential light-harvesting materials for efficient and cost-effective solar cells. However, the use of lead iodide in state-of-the-art perovskite devices may dem ...

Wiley-VCH Verlag GmbH2019

One-Year stable perovskite solar cells by 2D/3D interface engineering

Michael Graetzel, Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Giulia Grancini, Cristina Roldán Carmona

Despite the impressive photovoltaic performances with power conversion efficiency beyond 22%, perovskite solar cells are poorly stable under operation, failing by far the market requirements. Various technological approaches have been proposed to overcome ...

Nature Publishing Group2017

Nanoscale Mass-Spectrometry Imaging of Grain Boundaries in Perovskite Semiconductors

Mohammad Khaja Nazeeruddin, Hiroyuki Kanda, Tom Theodorus Antonius Lummen, Iwan Zimmermann, Paul Gratia

Incorporation of alkali metals such as Cs+, Rb+, and K+ into hybrid organic-inorganic halide lead perovskites (HOIPs) generally improves the optoelectronic properties of HOIPs. However, it is still uncertain how alkali metals interact and distribute within ...

2020

Non‐Planar and Flexible Hole‐Transporting Materials from Bis‐Xanthene and Bis‐Thioxanthene Units for Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Giulia Grancini

Two new hole‐transporting materials (HTMs), BX‐OMeTAD and BTX‐OMeTAD , based on xanthene and thioxanthene units, respectively, and bearing p ‐methoxydiphenylamine peripheral groups, are presented for their use in perovskite solar cells (PSCs). The novelty ...

Wiley-VHCA AG2019

Efficiency enhancement of perovskite solar cells via incorporation of phenylethenyl side arms into indolocarbazole-based hole transporting materials

Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Kasparas Rakstys

Small-molecule hole transporting materials based on an indolocar-bazole core were synthesized and incorporated into perovskite solar cells, which displayed a power conversion efficiency up to 15.24%. The investigated hole transporting materials were synthe ...

Royal Soc Chemistry2016

Design of cyclopentadithiophene-based small organic molecules as hole selective layers for perovskite solar cells

Mohammad Khaja Nazeeruddin, Iwan Zimmermann

Thiophene-based p-type molecules are being extensively investigated and employed in optoelectronic devices due to their intriguing semiconducting properties. Herein, we report the synthesis and characterization of a 4H-cyclopenta[1,2-b: 5,4-b']dithiophene- ...

ROYAL SOC CHEMISTRY2018

Improved efficiency and reduced hysteresis in ultra-stable fully printable mesoscopic perovskite solar cells through incorporation of CuSCN into the perovskite layer

Mohammad Khaja Nazeeruddin, Giulia Grancini, Iwan Zimmermann, Paul Gratia

Fully printable hole transport layer-free mesoscopic perovskite solar cells have proven excellent long-term stability and are therefore promising candidates for scale-up to larger modules required for the commercialization of the perovskite photovoltaic te ...

Royal Society of Chemistry2019

Synthesis and Photophysical Characterization of Cyclometalated Ruthenium Complexes with N-Heterocyclic Carbene Ligands

Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Sadig Aghazada, Valeriu Scutelnic

In the search of new ligand environment for the ruthenium(II) complexes with pyridine-type ligands, we developed seven new cyclometalated ruthenium complexes with N-heterocyclic carbenes (NHCs). In a two-step procedure, we synthesized complexes with the ge ...

American Chemical Society2017

Charge transporting material for optoelectronic and/or photoelectrochemical devices

Michael Graetzel, Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Paul Gratia, Inés Garcia Benito

The present invention relates to an optoelectronic and/or photoelectrochemical device comprising at least one organic-inorganic perovskite as sensitizer and at least one compound of formula (I) comprising one benzotrithiophene core Q, wherein each thiophen ...

2017

Development of an inorganic cesium carbonate-based electron transport material for a 17% power conversion efficiency perovskite solar cell device

Mohammad Khaja Nazeeruddin, Tom Theodorus Antonius Lummen, Iwan Zimmermann

A low-temperature solution process technique is employed to develop an inorganic cesium carbonate (Cs2CO3) as an electron transport material for inorganic-organic hybrid double cation (FAPbI(3))(0.85)(MAPbBr(3))(0.15) perovskite solar cells, as an alternat ...

2020