Self-Assembling Oxide Catalyst for Electrochemical Water Splitting
Daniel S. Bick, Andreas Kindsmueller, Deok-Yong Cho, Ahmed Yousef Mohamed, Thomas Bredow, Hendrik Laufen, Felix Gunkel, David N. Mueller, Theodor Schneller, Rai… 展开作者
Daniel S. Bick, Andreas Kindsmueller, Deok-Yong Cho, Ahmed Yousef Mohamed, Thomas Bredow, Hendrik Laufen, Felix Gunkel, David N. Mueller, Theodor Schneller, Rainer Waser, Ilia Valov
备注：
24 pages, 3 Figures and 5 Extended Data Figures, 1 Table, including Suplementary Information
Renewable energy conversion and storage, and greenhouse gas emission-free technologies are within the primary tasks and challenges for the society. Hydrogen fuel, produced by alkaline water electrolysis is fulfilling all these demands, however the technology is economically feeble, limited by the slow rate of oxygen evolution reaction. Complex metal oxides were suggested to overcome this problem being low-cost efficient catalysts. However, the insufficient long-term stability, degradation of structure and electrocatalytic activity are restricting their utilization. Here we report on a new perovskite-based self-assembling material BaCo0.98Ti0.02O3-$δ$:Co3O4 with superior performance, showing outstanding properties compared to current state-of-the-art materials without degeneration of its properties even at 353 K. By chemical and structural analysis the degradation mechanism was identified and modified by selective doping. Short-range order and chemical composition rather than long-range order are factors determining the outstanding performance. The derived general design rules can be used for further development of oxide-based electrocatalytic materials.
In this work, we provide a computational methodological framework using the single-atom systems as an example material class for ammonia synthesis that is robust towards parameter selection. Applying this to Pt$_1$/g-C$_3$N$_4$, Ru$_1$/g-C$_3$N$_4$, and Fe$_1$/g-C$_3$N$_4$, we generate ensembles of limiting potentials, using the ensemble of functionals collected via Bayesian Error Estimation Functionals (BEEF), to robustly predict catalytic activity. We then extend this to study the scaling between NRR reaction intermediates and use it to identify that NNH* as the best descriptor for these rel…
A continuous CO2 vapor-fed electrochemical cell prototype that performs CO2R with high faradaic efficiency for desired carbon products for up to 72 hours of operation is presented. The cell design facilitates a flow through configuration, capitalizing on gas diffusion electrode (GDE) and membrane electrode architecture (MEA) without requiring a catholyte. We demonstrate stable performance and design adaptability by incorporating various CO2R catalysts and membranes into the cell, investigating lifetime performance and selectivity under established experimental conditions. With an Ag foil and P…
This manuscript represents an investigation of structure, property and electrochemical activity for commercially available RuO2 coated titanium electrode, known as DSA. The investigation mainly aimed at XAS studies to understand the hidden structural information for RuO2. Two different (150 micron) and a (6 micron) titanium metal coated with RuO2 was exposed at ex-situ and in-situ XAS experiment to find out its electrocatalytic property and corrosion during chlorine generation reaction. A detailed survey of XANES and EXAFS showed that the stable RuO2 formed a nano cluster during chlorine gener…
Cobalt-porphyrin catalyzed reductive decomposition of CO2 to CO is investigated based on Koper's water facilitated CO2 reduction mechanism using a simple but accurate protocol based on thermodynamics. In our protocol, accurate predictions of standard redox potentials and free energy differences are achieved by combining strengths of both density functional theory and experimental observations. With the proposed protocol, we found that the proton transfer from H2O takes place at -0.80 V vs. RHE at pH=3 through a concerted pathway and, as a result, the key intermediate for the CO generation, i.e…
Pt/Graphene and Pt/MnO2-Graphene catalysts have been prepared by microwave-assisted polyol process. Electrochemical results show that Pt/MnO2-Graphene has higher electrocatalytic activity and stability. Furthermore, carbon riveted Pt/MnO2-Graphene catalyst has been designed and synthesized on the basis of in situ carbonization of L-ascorbic acid. The stability for carbon riveted Pt/MnO2-catalyst is significantly enhanced.
Clean hydrogen production through efficient and cost-effective electrochemical water splitting is highly promising to meeting future global energy demands. The design of Earth-abundant materials with both high activity for hydrogen evolution reaction (HER) and electrochemical stability in both acidic and alkaline environments summarize the outcomes needed for practical applications. Here, we report a non-noble 3d metal Cl-chemical doping of liquid phase exfoliated single/few-layer flakes of MoSe2 for creating MoSe2 nanoflakes/3d metal oxide-hydr(oxy)oxide hybrid HER-catalysts. We propose that …
Proton-electron coupled catalyst for ionomer-free electrochemical energy conversion
University of California, Los Angeles（加州大学洛杉矶分校）；Georgia Institute of Technology（佐治亚理工学院）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Max Planck Institute for Dynamics of Complex Technical Systems（马克斯·普朗克复杂技术系统动力学研究所）；California NanoSystems Institute（加州纳米系统研究所）；California Institute of Technology（加州理工学院）
The requirements for beneficial materials restructuring into a higher performance OER electrocatalyst are still a largely open question. Here we use Erythrite (Co$_3$(AsO$_4$)$_2\cdot$8H$_2$O) as a Co-based OER electrocatalyst to evaluate its catalytic properties during in-situ restructuring into an amorphous Co-based catalyst in four different electrolytes at pH 7. Using diffraction, microscopy and spectroscopy, we observed a strong effect in the restructuring kinetics depending of the anions in the electrolyte. Only carbonate electrolyte could activate the catalyst electrode, which we relate…
Defect-Engineered h-BN as a Platform for Single-Atom HER Catalysts: Descriptor Screening Refined by Electrochemical Stability Analysis
University of Belgrade − Faculty of Physical Chemistry（贝尔格莱德大学物理化学学院）；Luleå University of Technology（吕勒奥理工学院）；Serbian Academy of Sciences and Arts（塞尔维亚科学与艺术院）
MoS2 are facile, stable, non-toxic, affordable materials with reasonable price, and have exhibit its superior potential in catalysis, sensing, opt electrochemical, environmental relate application1, etc. Modification of MoS2 materials has been widely applied for adjusting and formulate the relative performance in certain application field. Making vacancy, doping with other atoms, expending of the layer space, heterojunction engineering, phase engineering etc. have been applied to facilitate the catalytic hydrogen evolution performance. We make a detailed summary on MoS2 characterization method…
Methylene blue (MB) is often used in textile industries and is actively present in the wastewater runs-off. Recently, mediated electrochemical oxidation (MEO) offers a fast, reliable and promising results for environmental remediation. Thus, we aimed to evaluate the electro-degradation potential of MB by MEO using Ce(IV) ionic mediator. Furthermore, we also observed the influence of addition Ag(I) ion catalyst in MEO for degradation of MB. The electro-degradation of MB was evaluated by cyclic voltammetry technique and was confirmed by UV-Vis spectrophotometry, high performance liquid chromatog…
The design of efficient and cost-effective catalysts for the hydrogen evolution reaction (HER) is the key for molecular hydrogen (H2) production from electrochemical water splitting. Transition metal dichalcogenides (MX2), most notably group-6 MX2 (e.g., MoS2 and WS2), are appealing catalysts for the HER alternative to the best, but highly expensive, Pt-group elements. However, their HER activity is typically restricted to their edge sites rather than their basal plane. Furthermore, their semiconducting properties hinder an efficient electron transfer to the catalytic sites, which impedes a hi…
The CO_{2} electro-reduction reaction (CORR) is a promising avenue to convert greenhouse gases into high-value fuels and chemicals, in addition to being an attractive method for storing intermittent renewable energy. Although polycrystalline Cu surfaces have long known to be unique in their capabilities of catalyzing the conversion of CO_{2} to higher-order C1 and C2 fuels, such as hydrocarbons (CH_{4}, C_{2}H_{4} etc.) and alcohols (CH_{3}OH, C_{2}H_{5}OH), product selectivity remains a challenge. In this study, we select three metal catalysts (Pt, Au, Cu) and apply in situ surface enhanced i…
MXenes are a class of 2D/layered materials which are highly conductive, hydrophilic, have a large electrochemical surface area and are easily processible into electrodes for energy applications. Since the discovery of MXenes over ten years ago, these materials have been mainly used in the preparation of electrodes for batteries and supercapacitors. However, due to their aforementioned properties, MXenes could potentially be utilised as a component in the catalyst layer for the Oxygen Evolution Reaction (OER). This opinion piece will discuss some of the recent literature in the area of hybrid c…
Nonylphenol ethoxylate (NPE 10) is a non ionic surfactant which is synthesized from alkylphenol ethoxylate. The accumulation of NPE-10 in wastewater will endanger the ecosystem as well as human being. At present, by an advancement of technology NPE 10 can be degraded indirectly by using an electrochemically treatment. Thus, this study aimed to evaluate the potential electrodegradation of NPE 10 by mediated electrochemical oxidation (MEO) using Ce(IV) ionic mediator. In addition, the influence of Ag(I) ionic catalyst in the performance of MEO for degradation of NPE 10 was also observed. The pot…
Mechanistic Insights into Active Sites for Electrochemical CO2 and CO Reduction over the Strain-Engineered Dealloyed Cu
Imperial College London（帝国理工学院）；Univ Rouen Normandie, CNRS, INSA Rouen Normandie, Groupe de Physique des Matériaux（鲁昂诺曼底大学，法国国家科学研究中心，鲁昂诺曼底国立应用科学学院，材料物理研究组）；The European Synchrotron - ESRF（欧洲同步辐射装置）；Oxford University（牛津大学）
Functional properties of transition-metal oxides strongly depend on crystallographic defects. In transition-metal-oxide electrocatalysts such as SrIrO3 (SIO), crystallographic lattice deviations can affect ionic diffusion and adsorbate binding energies. Scanning x-ray nanodiffraction enables imaging of local structural distortions across an extended spatial region of thin samples. Line defects remain challenging to detect and localize using nanodiffraction, due to their weak diffuse scattering. Here we apply an unsupervised machine learning clustering algorithm to isolate the low-intensity dif…
We present an electron tomography method that allows for the identification of hundreds of electrocatalyst nanoparticles with one-to-one correspondence before and after electrochemical aging. This method allows us to track, in three-dimensions (3-D), the trajectories and morphologies of each Pt-Co nanocatalyst on a fuel cell carbon support. The use of atomic-scale electron energy loss spectroscopic imaging enables the correlation of performance degradation of the catalyst with changes in particle/inter-particle morphologies, particle-support interactions and the near-surface chemical compositi…
Combining first-principles modeling and symbolic regression for designing efficient single-atom catalysts in Oxygen Evolution Reaction on Mo$_2$CO$_2$ MXenes
该研究结合第一性原理建模、ESSI 分析与符号回归，筛选 Mo$_2$CO$_2$ MXenes 上的 OER 单原子催化剂，发现 Cu 过电位最低，并提取关键描述符与过电位公式。
The Key Steps and Distinct Performance Trends of Pyrrolic vs. Pyridinic M-N-C Catalysts in Electrocatalytic Nitrate Reduction
Advanced Institute for Materials Research (WPI-AIMR), Tohoku University（东北大学物质材料研究创新世界首脑研究所）；School of Chemical and Biomolecular Engineering, The University of Sydney（悉尼大学化学与生物分子工程学院）；State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences（中国科学院长春应用化学研究所稀土资源利用国家重点实验室）；School of Applied Chemistry and Engineering, University of Science and Technology of China（中国科学技术大学应用化学与工程学院）
Advanced materials for electrocatalytic and photoelectrochemical water splitting are central to the area of renewable energy. Here, we developed a solvothermal synthesis of MoS2 nanoparticles selectively on reduced graphene oxide (RGO) sheets suspended in solution. The resulting MoS2/RGO hybrid material possessed nanoscopic few-layer MoS2 structures with abundant exposed edges stacked onto graphene, in strong contrast to large aggregated MoS2 particles grown freely in solution without GO. The MoS2/RGO hybrid exhibited superior electrocatalytic activity in the hydrogen evolution reaction (HER) …
The development of active catalysts for hydrogen evolution reaction (HER) made from low-cost materials constitutes a crucial challenge in the utilization of hydrogen energy. Earth-abundant molybdenum disulfide (MoS$_2$) has been discovered recently with good activity and stability for HER. In this report, we employed the hydrothermal technique for MoS$_2$ synthesis which is a cost-effective and environmentally friendly approach and has the potential for future mass production. To investigate the structure-property relationship, scanning electron microscope (SEM), transmission electron microsco…
Improving the stability of electrocatalysts for the oxygen evolution reaction (OER) through materials design has received less attention than improving their catalytic activity. We explored the effect of Mn addition to a cobalt oxide for stabilizing the catalyst by comparing Na-containing CoOx and (Co0.7Mn0.3)Ox films electrodeposited in alkaline solution. The obtained disordered films were classified as layered oxides using X-ray absorption spectroscopy (XAS). The CoOx films showed a constant decrease in the catalytic activity during cycling, confirmed by oxygen detection, while that of (Co0.…
Dissolution of electrocatalysts during long-term and dynamic operation is a challenging problem in energy conversion and storage devices such as fuel cells and electrolyzers. To develop stable electrocatalysts, we adopt the design concept of segregation engineering, which uses solute segregation prone to electrochemical dissolution at internal defects, i.e., grain boundaries and dislocations. We showcase the feasibility of this approach by stabilizing a model Pt catalyst with an addition of more noble Au (approximately 5 atomic percent). We characterized the defects' nanoscale structure and ch…
Energy demands of modern society require efficient means of energy conversion and storage. Nanocarbons have been identified as versatile materials which combine many desirable properties, allowing them to be used in electrochemical power sources, from electrochemical capacitors to fuel cells. Efficient production of nanocarbons requires innovative and scalable approaches which allow for tuning of their physical and chemical properties. Carbonization of polymeric nanostructures has been demonstrated as a promising approach for production of high-performance nanocarbons with desired morphology a…
Large scale production of hydrogen by electrochemical water splitting is considered as a promising technology to address critical energy challenges caused by the extensive use of fossil fuels. Although nonprecious nickel-based catalysts work well at low current densities, they need large overpotentials at high current densities that hinders their potential applications in practical industry. Here we report a hydroxide-mediated nickel based electrocatalyst for high current density hydrogen evolution, which delivers a current density of 1000 mA cm-2 at an overpotential of 98 mV. Combined X-ray a…
Electrochemical water splitting is an environmentally friendly technology to store renewable energy in the form of chemical fuels. Among the earth-abundant first-row transition metal-based catalysts, mixed Ni-Fe oxides have shown promising performance for effective and low-cost catalysis of the oxygen evolution reaction (OER) in alkaline media, but the synergistic roles of Fe and Ni cations in the OER mechanism remain unclear. In this work, we report how addition of Ni changes the reactivity of a model iron oxide catalyst, based on Ni deposited on and incorporated in a magnetite Fe3O4 (001) si…
Efficient electro-catalytic water-splitting technologies require suitable catalysts for the oxygen evolution reaction (OER). The development of novel catalysts could benefit from the achievement of a complete understanding of the reaction mechanism on iridium oxide (IrO$_2$), an active catalyst material that is, however, too scarce for large-scale applications. Considerable insight has already been provided by \emph{operando} X-ray absorption near-edge structure (XANES) experiments, which paved the way towards an atomistic description of the catalyst's evolution in a working environment. We co…
Hydrogen is a promising energy carrier and key agent for many industrial chemical processes1. One method for generating hydrogen sustainably is via the hydrogen evolution reaction (HER), in which electrochemical reduction of protons is mediated by an appropriate catalyst-traditionally, an expensive platinum-group metal. Scalable production requires catalyst alternatives that can lower materials or processing costs while retaining the highest possible activity. Strategies have included dilute alloying of Pt2 or employing less expensive transition metal alloys, compounds or heterostructures (e.g…
Unraveling a descriptor that is correlated with catalytic reactivity is essential for fast screening for the optimal catalysts for a given catalytic reaction. Herein, we propose bond-derived orbitalwise coordination number ($\overline{CN}^α$, $α$= $s$ or $d$) as a simple and accurate descriptor used for transition metal (TM) oxides that takes into account both geometrical and electronic structures around active sites, and avoids excessive computation burden. This descriptor has a strong scaling relation with the activity in oxygen electrochemistry, enabling us to readily screen for the optimal…
A copper sulfide-hydroxypropyl $β$-Cyclodextrin-reduced graphene oxide composite for highly sensitive electrochemical detection of 5-hydroxytryptamine in biological samples
The design of better heterogeneous catalysts for applications such as fuel cells and electrolyzers requires a mechanistic understanding of electrocatalytic reactions and the dependence of their activity on operating conditions such as pH. A satisfactory explanation for the unexpected pH dependence of electrochemical properties of platinum surfaces has so far remained elusive, with previous explanations resorting to complex co-adsorption of multiple species and resulting in limited predictive power. This knowledge gap suggests that the fundamental properties of these catalysts are not yet under…
However, their electrocatalytic activity is still poorly understood. This work deciphers the origin of the catalytic activity of counter-electrodes (CEs)/current collectors made of self-standing carbon nanotubes fibers (CNTfs) using Co$^(+2)$/Co$^(+3)$ redox couple electrolytes. This is based on comprehensive electrochemical and spectroscopic characterizations of fresh and used electrodes applied to symmetric electrochemical cells using platinum-based CEs as a reference. As the most relevant findings, two straight relationships were established: i) the limiting current and stability increase r…
Ordered W-doped Ta2O5 nanotube arrays were grown by self-organizing electrochemical anodization of TaW alloys with different tungsten concentrations and by a suitable high temperature ammonia treatment, fully converted to W:Ta3N5 tubular structures. A main effect found is that W doping can decrease the band gap from 2 eV (bare Ta3N5) down to 1.75 eV. Ta3N5 nanotubes grown on 0.5 at% W alloy and modified with (CoOH)x as co-catalyst show ~33% higher photocurrents in photoelectrochemical (PEC) water splitting than pure Ta3N5.
Water splitting allows the storage of solar energy into chemical bonds (H2+O2) and will help to implement the urgently needed replacement of limited available fossil fuels. Particularly in neutral environment electrochemically initiated water splitting suffers from low efficiency due to high overpotentials caused by the anode. Electro-activation of X20CoCrWMo10-9, a Co-based tool steel resulted in a new composite material (X20CoCrWMo10-9//Co3O4) that catalyzes the anode half-cell reaction of water electrolysis with a so far unequalled effectiveness. The current density achieved with this new a…
Active, selective and stable catalysts are imperative for sustainable energy conversion, and engineering materials with such properties are highly desired. High-entropy alloys (HEAs) offer a vast compositional space for tuning such properties. Too vast, however, to traverse without the proper tools. Here, we report the use of Bayesian optimization on a model based on density functional theory (DFT) to predict the most active compositions for the electrochemical oxygen reduction reaction (ORR) with the least possible number of sampled compositions for the two HEAs Ag-Ir-Pd-Pt-Ru and Ir-Pd-Pt-Rh…
Mechanistic Insights into Enhanced Alkaline Oxygen Evolution on Zn-Al Alloy Electrodes
Bangladesh University of Engineering and Technology（孟加拉国工程与技术大学）；Institute of Energy Research and Development (IERD) Bangladesh Council of Scientific and Industrial Research (BCSIR)（能源研发研究所 孟加拉国科学和工业研究委员会）
Ammonium tetrathiomolybdate (ATM) spontaneously self assembles on Au electrodes forming a hydrophilic, air stable, pH (3-11) tolerant multilayer that is stable over a reasonably large potential window. The ATM functionalized Au electrodes can adsorb iron porphyrin catalysts and act as O2 reducing electrodes. These electrodes are stable enough to perform rotating disk electrochemistry (RDE) as well as rotating ring disk electrochemistry (RRDE) experiments. The X-ray photoelectron spectroscopy (XPS) data indicate that the sulphide atoms of ATM anchors a single ATM layer on to Au and the subseque…
The oxygen evolution reaction (OER) plays an important role in evaluating a photocatalyst and to understand its surface chemistry. In this work we present a comparative study of the OER on the oxide NaTaO$_3$ (113) surface and the oxynitride SrTaO$_2$N (001) surface. Oxynitrides are highly promising photocatalysts due to their smaller band gap and resulting better visible light absorption compared to oxides but our knowledge about their surface structure and chemistry is still very limited. With the goal to compare the surface chemistry of oxides and oxynitrides, we perform density functional …
