Modulation of Ionically Generated Space Charge Effects at Hybrid Perovskite and Oxide Interfaces via Surface Modification

Advanced Materials Interfaces

Published On 2024

Interfacial space charges significantly influence transport and recombination of charge carriers in optoelectronic devices. Due to the mixed ionic‐electronic conducting properties of halide perovskites, not only electronic effects, but also ionic interactions at their interfaces need to be considered in the analysis of space charges. Understanding of these interactions and their control is currently missing. This study elucidates the ionic effects on space charge formation at the interface between methylammonium lead iodide (MAPI) and alumina, and its modulation through surface modification using organic molecules. Embedding insulating alumina nanoparticles within MAPI films leads to enhancement of the electronic conductivity. This effect is consistent with the formation of an interfacial inversion layer in MAPI and can only be explained on the basis of ionic interactions. Such an effect is attenuated by surface …

Journal

Advanced Materials Interfaces

Published On

2024

Page

2300874

Authors

Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Position

Professor

H-Index(all)

299

H-Index(since 2020)

170

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Solar energy conversion

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

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École Polytechnique Fédérale de Lausanne

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Research data supporting" High carrier mobility along the [111] orientation in Cu2O photoelectrodes"

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Michael Graetzel

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École Polytechnique Fédérale de Lausanne

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Energy & Environmental Materials

High‐Performance Perovskite Solar Cells with Zwitterion‐Capped‐ZnO Quantum Dots as Electron Transport Layer and NH4X (X = F, Cl, Br) Assisted Interfacial …

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Michael Graetzel

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École Polytechnique Fédérale de Lausanne

11th International Conference Photosynthesis and Hydrogen Energy Research for Sustainability

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

arXiv preprint arXiv:2308.03386

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Nature

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2023/10/19

Article Details
Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Dataset of" The Impact of Spacer Size on Charge Transfer Excitons in Dion-Jacobson and Ruddlesden-Popper Layered Hybrid Perovskites"

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Science

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Nature

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2023/12/14

Article Details
Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Angewandte Chemie

Exfoliated 2D Layered and Nonlayered Metal Phosphorous Trichalcogenides Nanosheets as Promising Electrocatalysts for CO2 Reduction

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Advanced Materials

Stabilization of FAPbI3 with Multifunctional Alkali‐Functionalized Polymer

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Michael Graetzel

Michael Graetzel

École Polytechnique Fédérale de Lausanne

Advanced Materials

Ion–Dipole Interaction Enabling Highly Efficient CsPbI3 Perovskite Indoor Photovoltaics

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Roberta Maia Sabino

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Advanced Materials Interfaces

Polydopamine‐Mediated, Amphiphilic Poly(Carboxybetaine Methacrylamide‐r‐Trifluoroethyl Methacrylate) Coating with Resistance to Marine Diatom Adhesion …

Marine biofouling–the adhesion of marine organisms onto a ship hull–causes increased fuel consumption, leading to massive carbon dioxide emissions. Many attempts are made to address this issue, and antifouling polymer coatings are extensively investigated owing to their environmental friendliness. Zwitterionic polymers, polysaccharides, and polyethylene glycol are frequently used as surface coatings, demonstrating excellent marine antifouling performance. However, these hydrophilic polymer coatings have a major drawback: when exposed to sediment, various minerals are easily adsorbed by the coatings, causing them to lose their inherent antifouling properties. Amphiphilic polymer coatings have therefore been proposed as alternatives to hydrophilic polymer coatings. In this study, the synthesis of amphiphilic copolymers composed of carboxybetaine methacrylamide and trifluoroethyl methacrylate and …

Eider Berganza Eguiarte

Eider Berganza Eguiarte

Karlsruher Institut für Technologie

Advanced Materials Interfaces

Nanoscale Confinement of Dip‐Pen Nanolithography Written Phospholipid Structures on CuZr Nanoglasses

Nanoglasses have attracted considerable interest among material scientists due to their novel and surprising properties. However, there is still a significant gap in understanding how nanoglasses interact with biomaterials and their effects on living cells. Previous cell studies have reported indications of possible proliferation effects, but a comprehensive understanding of differentiating nanoglass influences from distinct material or topography effects is yet to be established. In this study, the interaction between nanoglass surfaces and phospholipids, which are fundamental components of cell membranes, is investigated. The findings reveal a unique stabilizing effect exhibited by nanoglasses on structures created using lipid dip‐pen nanolithography, preventing their spreading over the surface (“confinement”). This discovery suggests that nanoglasses can potentially influence the structure of cell membranes …

Zhen Tian

Zhen Tian

University of New Hampshire

Advanced Materials Interfaces

Melanin Zinc Complex as a Biocompatible Agent for Clearing Bacteremia

Sepsis, whole‐body inflammation caused by the contamination of blood by bacteria and endotoxins, affects millions of patients annually with high mortality rates. A recent promising approach to treat sepsis involves the removal of bacteria and endotoxins using extracorporeal blood‐cleansing devices. However, poor specificity, slow recognition of pathogens, and high costs remain the main limitations. Here, the melanin, a biologically derived pigment, is reported for the rapid binding of bacteria and endotoxins from the contaminated blood . This novel approach utilizes the specific binding between Zn2+‐loaded melanin and bacteria/endotoxins with minimal nonspecific interactions with human blood components. Melanin contains various chemical functional groups that allow reversible chelation of metallic ions such as Zn2+ via redox reactions. Zn2+ enables rapid and specific binding with bacteria/endotoxins due …

Paul Pigram

Paul Pigram

La Trobe University

Advanced Materials Interfaces

Profiling a Low Emissivity Glass Coating with ToF‐SIMS and Machine Learning

Characterization of multilayer coatings in 3D presents many challenges, as composition can change by area and by depth. Compositional characteristics of the interior of multilayer coatings emerge during analysis, so are frequently discovered only through exacting retrospective investigations. Time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) can be used to elucidate such complex systems; however, data analysis is a challenge. In this work a detail presentation is done of 3D chemical characterization of a low emissivity (low‐E) double silver coating on glass using ToF‐SIMS and machine learning. An unsupervised machine learning technique, the self‐organizing map with relational perspective mapping, is used to visualize the chemical similarity between different layers of the low‐E film. Repeating layers are easily identified at the single‐voxel level, based on their entire mass spectra, and are classified …

Hoang M. Nguyen

Hoang M. Nguyen

Aalto-yliopisto

Advanced Materials Interfaces

Bio‐Templated Silver Nanopatterns for Photothermal and Antifogging Coatings

Transparent photothermal coatings based on plasmonic noble metals often face a trade‐off between achieved temperatures and transmittances. This challenge arises from the fact that plasmonic nanoparticles (NPs), which rely on their size and structures, selectively absorb light of various wavelengths and convert it into heat. In the cases of randomly arranged plasmonic NPs, absorbances are predominantly in the visible range, leading to lowered transmittances. In this work, the self‐assembly behavior of a biotemplate containing flexible potato virus A (PVA) is used to produce network‐like surface patterns with controllable intermittent vacancies. These templates effectively anchor silver nanoparticles (AgNPs), forming dense arrays of plasmonic hotspots interspersed with vacant regions. With this approach, a temperature increase of 21 °C above ambient temperature under 1‐sun radiation is achieved while …

Xiaojiang Yu

Xiaojiang Yu

National University of Singapore

Advanced Materials Interfaces

Interfacial Electronic and Magnetic Reconstructions in Manganite/Titanate Superlattices

Complex oxide heterointerfaces provide a spacious arena for creating emergent phenomena that are unattainable in the constituent bulk counterparts. Herein, The BaTiO3/La1‐xSrxMnO3 [BTO/LSMO (x)] superlattice (SL) as a model system to investigate the intimately coupled interfacial effects and their resultant phenomena is focused on. The experimental and Density Functional Theory (DFT) calculations reveal that the induced magnetism on Ti originates from both the charge transfer process between Mn and Ti at the titanate/manganite heterointerfaces and the cation intermixing, both contributing comparably to the overall magnetic effect. Upon changing x, the orbital reconstruction of the Mn 3d electrons, tailored by the strain state of the LSMO (x) layers, efficiently modifies the magnetic exchange coupling between Mn–Ti and Mn–Mn at the interfaces, which are proved to account for the modulations of the …

Shengman Li

Shengman Li

Hunan University

Advanced Materials Interfaces

Small Molecule Additives to Suppress Bundling in Dimensional‐Limited Self‐Alignment Method for High‐Density Aligned Carbon Nanotube Array

Semiconducting single‐walled carbon nanotube (CNT) is a promising candidate as a channel material for advanced logic transistors, attributed to the ultra‐thin 1‐nm cylindrical geometry, high mobility, and high carrier injection velocity. However, the presence of undesired CNT bundles in the CNT arrays for wafer‐scale device fabrication, even when utilizing the state‐of‐the‐art dimension‐limited self‐alignment (DLSA) method, poses challenges. These CNT bundles degrade the transistor gate's efficiency in controlling the flow of charge carriers in the CNT channel, leading to pronounced device‐to‐device variability. Here, a novel method is introduced to alleviate bundling in CNT arrays assembled via DLSA, by involving small molecule additive to screen the attractive van der Waals force between neighboring CNTs during the DLSA process, resulting in over 50% reduction in CNT bundling. Furthermore, a …

Ahmed A Ibrahim

Ahmed A Ibrahim

King Saud University

Advanced Materials Interfaces

Process Optimization for Syngas Production from the Dry Reforming of Methane over 5Ni+ 3Sr/10Zr+ Al Catalyst Using Multiple Response Surface Methodology

5Ni+3Sr/10Zr+Al catalyst is synthesized using the impregnation method, characterized, and tested for dry reforming of methane. The influence of reaction temperature, feed ratio (CO2/CH4), and gas hour space velocity are examined using multiple response surface methodology through three factors in, a four‐level central composite design. Second and higher‐order regression models are applied to evaluate the interaction between the process parameters and responses. The results indicate that the reaction temperature is the most influential followed by the space velocity, while the feed ratio has a weak effect. The optimum values that maximize each of the response variables are found to be the reaction temperature at 746 °C, the space velocity of 12 000 ccg−1h−1, and the feed ratio of 0.958. Under these conditions, the predicted CH4 and CO2 conversions are 86.83% and 92.27%, respectively. While the H2/CO …