Article
Chemistry, Multidisciplinary
Jingyu Guan, Shaoxuan Yang, Tongtong Liu, Yihuan Yu, Jin Niu, Zhengping Zhang, Feng Wang
Summary: The development of platinum-based oxygen reduction reaction electrocatalysts with good resistance to poisoning is crucial for practical fuel cell applications. A surface-engineering approach using alloy PtBi shells to prepare nanostructured Pt alloys showed significantly improved ORR performance compared to benchmark Pt/C, with enhanced tolerance to methanol and carbon monoxide. The observed enhancement in performance is attributed to increased compressive strain and charge displacement via Pt-Bi bonding.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Multidisciplinary
Lijuan Zhang, Haichen Yuan, Xiang Li, Yan Wang
Summary: NiCo2O4@NiCo2O4 core-shell nanostructures anchored on Ni foam exhibit low overpotential and excellent stability as an oxygen evolution reaction catalyst.
Article
Chemistry, Physical
Lisa Royer, Antoine Bonnefont, Tristan Asset, Benjamin Rotonnelli, Juan-Jesus Velasco-Velez, Steven Holdcroft, Simon Hettler, Raul Arenal, Benoit Pichon, Elena Savinova
Summary: Transition metal oxides show promise as cost-effective catalysts for oxygen evolution reaction (OER) in alkaline media. However, understanding the transformations occurring under harsh oxidative OER conditions is crucial for developing stable and active catalysts. This study used NEXAFS spectroscopy to investigate the redox transformations of core-shell Fe3O4@CoFe2O4 oxide nanoparticles over a range of potentials. The analysis revealed that the Fe3O4 core significantly influences the surface chemistry of the CoFe2O4 shell during OER, with the Co (II) structure preserved even at high potentials where Co (II) is expected to be oxidized into Co (III), while Fe (II) in the core undergoes reversible oxidation to Fe (III).
Review
Chemistry, Multidisciplinary
Jin-Bo Pan, Sheng Shen, Lang Chen, Chak-Tong Au, Shuang-Feng Yin
Summary: Photoelectrochemical water splitting is a promising solution for solar energy conversion and storage, but the design of efficient photoanodes faces challenges. All known photoanode materials have drawbacks, with core-shell configurations showing potential for improved activity and stability. However, the mechanism for performance improvement still needs further examination.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yu Pei, David P. Wilkinson, Elod Gyenge
Summary: The authors investigated the electrochemical behavior and ORR/OER catalytic activity of core-porous shell Mn/Mn3O4 nanoparticles in comparison with other manganese dioxides (beta- and gamma-MnO2), and benchmarked against Pt/C and Pt/C-IrO2. They found that the core-shell Mn/Mn3O4 showed higher ORR and OER current density compared to the other MnO2 structures. To address the activity loss during potential cycling, they proposed an electrochemical activation method using Co(II) which resulted in superior activity and durability of the Co-incorporated Mn/Mn3O4. This study demonstrates the possibility of cost-effective ORR/OER catalysis.
Article
Chemistry, Physical
Linglan Men, Tiancong Shi, Jiao Li, Xiao Li, Bo Sun, Qingqing Pan, Zhongmin Su
Summary: In this work, a bimetallic nitride (Co/WN@NC) catalyst was prepared and exhibited outstanding catalytic performance and stability in both acidic and alkaline media, showing great potential for the development of simple transition metal-based electrocatalysts.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Multidisciplinary
Yi-Fan Cui, Si-Da Jiang, Qiang Fu, Ran Wang, Ping Xu, Yu Sui, Xian-Jie Wang, Zhi-Liang Ning, Jian-Fei Sun, Xun Sun, Alexander Nikiforov, Bo Song
Summary: In this study, a core-shell FeCoNiMoAl-based high-entropy alloy (HEA) was established as a promising electrocatalyst for oxygen evolution reaction (OER). The shell with crystalline-amorphous (c-a) heterostructure reduces the electron transfer resistance and generates more active sites, while the crystalline core improves the conductivity and self-supporting ability. The HEA electrodes show superior OER performance in terms of overpotential and stability, providing a potential route for highly efficient electrocatalysts in industrial water electrolysis and energy conversion processes.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Lin-Wei Chen, Fuxiang He, Ru-Yang Shao, Qiang-Qiang Yan, Peng Yin, Wei-Jie Zeng, Ming Zuo, Lixin He, Hai-Wei Liang
Summary: The study presents a low-Ir core-shell OER electrocatalyst with high activity in acidic media, showing a significantly improved OER performance compared to commercial Ir/C catalyst. The enhanced activity of the IrGa-IMC@IrOx catalysts is attributed to the modified electronic structure of IrOx induced by the intermetallic IrGa core, leading to improved adsorption capacity for O and OH binding and lower energy barrier for OER rate-determining steps.
Article
Chemistry, Physical
Zhaolong Wang, Hanxiang Chen, Jian Bao, Yanhua Song, Xiaojie She, Guoai Lv, Jiujun Deng, Huaming Li, Hui Xu
Summary: The development of a bifunctional electrode material with amorphous NiFeMo films grown on a conductive nickel foam substrate has significantly improved the overall water splitting performance, allowing for efficient hydrogen production to alleviate carbon emissions.
APPLIED SURFACE SCIENCE
(2023)
Article
Engineering, Environmental
Xinding Lv, Yan Li, Fei Deng, Haotong Li, Shutong Wan, Xue Han, Wanqi Zhang, Xia Tao
Summary: In this study, a protective layer of amorphous NiPOx/Fe(OH)3 was fabricated on the surface of NiP nanoarrays through a facile preoxidation tactic, resulting in improved oxygen evolution reaction (OER) performance of NiP. The optimized NiP@NiPOx/Fe(OH)3 electrode exhibited a low overpotential and long-term stability, which can be attributed to the synergy of the highly conductive NiP core and the NiPOx/Fe(OH)3 layer.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Analytical
Wenjuan Shi, Ah-Hyeon Park, Young-Uk Kwon
Summary: In this work, carbon-supported (Pd,Cu)@Pt core-shell nanoparticles with tunable Pt shell thickness are successfully synthesized by reacting pre-formed PdxCuy NPs with Pt(IV) ions. The catalysts exhibit enhanced catalytic activities and superior long-term durability, providing guidance for the commercialization of proton exchange membrane fuel cells.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Guoyu Shi, Tetsuro Tano, Donald A. Tryk, Miho Yamaguchi, Akihiro Iiyama, Makoto Uchida, Kazuo Iida, Chisato Arata, Sumitaka Watanabe, Katsuyoshi Kakinuma
Summary: This study investigates the OER catalytic performance of Ni-Co solid solution catalysts synthesized at different temperatures. Experimental results show that catalysts with amorphous or poorly crystalline oxide surfaces exhibit better OER activity at all temperatures, and the reduction of crystalline oxide phases can decrease the OER activation energy.
Article
Chemistry, Multidisciplinary
Jiao Liu, Peng Ding, Zexuan Zhu, Wei Du, Xiaoyong Xu, Jingguo Hu, Yong Zhou, Haibo Zeng
Summary: Transition metal-based catalysts undergo surface reconstruction to generate active sites for high OER performance. This study proposes using self-reconstruction as an efficient strategy to develop novel OER catalysts by designing pre-catalysts with flexible components susceptible to OER conditions. By constructing NiFe-based LDHs intercalated with MoO42- anions and achieving complete ECSR into active NiFeOOH, the catalyst showed excellent OER performance and durability, indicating the potential of ECSR engineering in component-flexible precursors for developing highly active OER catalysts.
Article
Engineering, Environmental
Xiaohong Gao, Jieli Chen, Yanhui Yu, Fangyuan Wang, Xiao Wu, Xingbo Wang, Weihua Mao, Jing Li, Wei Huang, Qi Chen, Ruisong Li, Chenghang You, Shaolei Wang, Xinlong Tian, Zhenye Kang
Summary: In this work, core-shell structured nanoarrays (NiTe@FeOOH) were designed and constructed for efficient overall seawater splitting. The catalyst exhibited superior performance in both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with low overpotentials and excellent durability. The strong interactions between NiTe and FeOOH, as well as the surface charge effect, contribute to its high activity and stability.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Xuan Liu, Siyang Zhang, Jiashun Liang, Shenzhou Li, Hao Shi, Jinjia Liu, Tanyuan Wang, Jiantao Han, Qing Li
Summary: In this study, protrusion-rich Cu@NiRu core@shell nanotubes were synthesized using a facile wet chemistry method and employed for hydrogen evolution reaction (HER) in an alkaline environment. The protrusion-like RuNi alloy shells with large surface area and abundant defects optimize the surface electronic structure through electron transfer and are effectively stabilized by the unique 1D hollow structure.
Article
Materials Science, Multidisciplinary
Zhongbo Li, Harald Rose, Jacob Madsen, Johannes Biskupek, Toma Susi, Ute Kaiser
Summary: We present a novel method to improve the computational efficiency of (S)TEM image simulation by diagonalizing the mixed envelope function (MEF) using matrix diagonalization. By incorporating the aperture function, only a small number of eigenvectors are needed to approximate the original matrix with high accuracy, resulting in significant reduction in computation time.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Chemistry, Physical
Georgina E. Shillito, Sven Rau, Stephan Kupfer
Summary: Quantum chemical methods were used to study the kinetics and thermodynamics of charge recombination in Ru-II based molecular photocatalysts. By selectively tuning the Ru-II coordination sphere, the charge transfer towards the bridging ligand during photoexcitation was promoted. This design method could potentially enhance the quantum efficiency of light-driven catalysis by promoting targeted electron transfer pathways and reducing deactivation pathways.
Article
Chemistry, Multidisciplinary
Yupeng Zhao, Dandan Gao, Si Liu, Johannes Biskupek, Ute Kaiser, Rongji Liu, Carsten Streb
Summary: Efficient and stable oxygen evolution reaction (OER) catalysts based on noble-metal-free materials are crucial for energy conversion and storage. This study demonstrated the conversion of polyoxometalate (POM)-doped ZIF-67 into a stable oxygen evolution electrocatalyst through chemical etching, cation exchange, and thermal annealing steps. Characterization techniques confirmed the synthesis of POM-doped ZIF-67 derived carbon-supported metal oxides, which exhibited structural and compositional advantages leading to low overpotential (306 mV at j=10 mA center dot cm(-2)) and long-term stability under harsh OER conditions (1.0 M aqueous KOH).
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Sebastian Knoll, Matthias Haenle, Alexander K. Mengele, Dieter Sorsche, Sven Rau, Carsten Streb
Summary: CLICK-chemistry is used to covalently link organic molecules with azides and alkynes. This study demonstrates the attachment of oligoaromatic organic moieties to Dawson-type polyoxometalates using CLICK-chemistry. The versatility and supramolecular chemistry of these systems are explored, and the charge-transfer behavior is found to depend on the size of the oligoaromatic pi-system.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Daniel Costabel, Afshin Nabiyan, Avinash Chettri, Franz Jacobi, Magdalena Heiland, Julien Guthmuller, Stephan Kupfer, Maria Waechtler, Benjamin Dietzek-Ivansic, Carsten Streb, Felix H. Schacher, Kalina Peneva
Summary: We present a photocatalytic setup using the organic photosensitizer diiodo-BODIPY, the non-precious-metal-based hydrogen evolution reaction catalyst (NH4)2[Mo3S13], and a polyampholytic unimolecular matrix poly(dehydroalanine)-graft-poly(ethylene glycol) in water. The system exhibits remarkable performance with high turnover numbers (TON > 7300) and turnover frequencies (TOF > 450 h-1), comparable to noble-metal-containing systems. Excited-state absorption spectra confirm the formation of a long-lived triplet state of the photosensitizer in both water and organic media. This system serves as a blueprint for developing noble-metal-free hydrogen evolution reaction in water, allowing for component optimization by modifying the substituent of the photosensitizer and the composition of the catalyst.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Chemistry, Multidisciplinary
Martin Laemmle, Alexander K. K. Mengele, Georgina E. E. Shillito, Stephan Kupfer, Sven Rau
Summary: In recent decades, research on artificial photocatalysis aiming to mimic natural photosynthesis has focused on reducing fossil fuel consumption through efficient solar energy harvesting. However, the instability problems of catalysts during light-driven operation are major challenges for industrial-scale implementation. This review discusses the structure-catalyst-stability relationships of di- and oligonuclear photocatalysts with different bridging ligand architectures, as well as the effects of ligands on catalytic centers and their implications for catalytic activity in intermolecular systems, providing important insights for the future design of operationally stable catalysts.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Editorial Material
Chemistry, Multidisciplinary
Carsten Streb
Summary: The atomically precise assembly of metal nanoparticles provides great opportunities for materials chemistry. Ring-shaped polyoxometalates have been used to stabilize Ag-30 nanoparticles with exposed surfaces.
Article
Energy & Fuels
Benedikt Bagemihl, Andrea Pannwitz, Sven Rau
Summary: Donor-photosensitizer-acceptor triads with 1,4-dihydro-N-benzyl-nicotinamide (BNAH) as the donor and N-methyl-4,4'-bipyridinium (MQ(+)) as the acceptor were synthesized by covalently functionalizing tris-heteroleptic ruthenium(II) complexes using copper-catalyzed click chemistry. The light-induced intramolecular electron transfer and long-lived charge-separated states of these triads were characterized using spectroscopy and electrochemistry. It was observed that the charge-separated state resides on different parts of the molecule within these two triads, allowing for selective directionality of charge transfer within a molecule.
Review
Chemistry, Multidisciplinary
Samar Batool, Marcel Langer, Stephen Nagaraju Myakala, Magdalena Heiland, Dominik Eder, Carsten Streb, Alexey Cherevan
Summary: This review summarizes prominent examples of thiomolybdate-based electro- and photocatalysis and provides a comprehensive analysis of their reactivities under homogeneous and heterogenized conditions. The study examines the active sites of thiomolybdates relevant for the hydrogen evolution reaction and discusses the shift from solution-phase to surface-supported thiomolybdates with a focus on applications in electrocatalysis and photocatalysis.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Shujun Li, Yubin Ma, Yue Zhao, Rongji Liu, Yupeng Zhao, Xusheng Dai, Nana Ma, Carsten Streb, Xuenian Chen
Summary: The study demonstrates the activation of molecular hydrogen by polyoxometalate (POM)-based heterogeneous compounds functionalized with Platinum particles. The synergism between a hydrogen spillover mechanism and electron-proton transfer by the POM enables the selective catalytic reduction of olefins and nitroarenes with high functional group tolerance.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Lukas Fridolin Pfeiffer, Yueliang Li, Manuel Mundszinger, Jonas Geisler, Claudia Pfeifer, Daria Mikhailova, Ahmad Omar, Volodymyr Baran, Johannes Biskupek, Ute Kaiser, Philipp Adelhelm, Margret Wohlfahrt-Mehrens, Stefano Passerini, Peter Axmann
Summary: In this study, the aging effects of sodium cathode materials for sodium-ion batteries (SIBs) were investigated. The study identified the causes of increased polarization and loss of active material, and provided insights for the development of future stable cathode materials for SIBs.
CHEMISTRY OF MATERIALS
(2023)
Article
Multidisciplinary Sciences
Stefan Repp, Moritz Remmers, Alexandra Stefanie Jessica Rein, Dieter Sorsche, Dandan Gao, Montaha Anjass, Mihail Mondeshki, Luca M. Carrella, Eva Rentschler, Carsten Streb
Summary: In this study, a coupled set of light-dependent and light-independent reaction equilibria controlling the mono- and di- metal-functionalization of a prototype molecular vanadium oxide cluster is reported. Mechanistic analyses reveal that coordination of a Mg2+ ion leads to the formation of mono-functionalized compound and release of a placeholder cation. Irradiation with visible light results in one-electron reduction, exchange of the second placeholder cation, and formation/crystallization of the di-metal-functionalized compound. Furthermore, the study demonstrates the feasibility of applying this synthetic concept to other metal cations.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Jonas Eichhorn, Patricia Hofmann, Benedikt Bagemihl, Carsten Streb, Sven Rau, Felix H. Schacher
Summary: In this study, molecular ruthenium (II) photosensitizers were covalently embedded within block copolymer micelles for light-driven catalysis with excellent performance in hydrogen evolution reaction (HER) using molecularly dissolved thiomolybdate clusters. The block copolymers, PS-b-P(ClHPMA-co-MMS) and PS-b-P(bpyHPMA-co-MMS), were synthesized and functionalized with ruthenium (II) polypyridyl complex, and self-assembled into ruthenium-functionalized block copolymer micelles. The colloidal system outperformed the homogeneous reference in the hydrogen evolution reaction.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Inorganic & Nuclear
Stefan Repp, Kim Lara Junginger, Dieter Sorsche, Theresa Zorn, Ann-Christin Poeppler, Yuji Kikukawa, Yoshihito Hayashi, Carsten Streb
Summary: The self-assembly of polyoxometalates (POMs), molecular metal oxides, can be controlled by internal or external templates. This study explores how the interaction between internal templates (halides, oxoanions) and external organic templates (protonated cyclene species) affects the self-assembly of a model polyoxovanadate cluster. Crystallographic analyses, spectroscopic studies, and V-51 NMR spectroscopy provide insights into the formation of an intermediate vanadate species during the process. These findings contribute to the development of template-driven synthetic chemistry of polyoxovanadates.
DALTON TRANSACTIONS
(2023)