scholarly journals Rationally designed indium oxide catalysts for CO2 hydrogenation to methanol with high activity and selectivity

2020 ◽  
Vol 6 (25) ◽  
pp. eaaz2060 ◽  
Author(s):  
Shanshan Dang ◽  
Bin Qin ◽  
Yong Yang ◽  
Hui Wang ◽  
Jun Cai ◽  
...  
Keyword(s):  
Density Functional ◽  
Rational Design ◽  
Density Functional Theory Calculations ◽  
Catalytic Performance ◽  
Oxide Catalysts ◽  
Great Promise ◽  
Experimental Realization ◽  
Successful Case ◽  
Catalytic Stability ◽  
Pure Phases

Renewable energy-driven methanol synthesis from CO2 and green hydrogen is a viable and key process in both the “methanol economy” and “liquid sunshine” visions. Recently, In2O3-based catalysts have shown great promise in overcoming the disadvantages of traditional Cu-based catalysts. Here, we report a successful case of theory-guided rational design of a much higher performance In2O3 nanocatalyst. Density functional theory calculations of CO2 hydrogenation pathways over stable facets of cubic and hexagonal In2O3 predict the hexagonal In2O3(104) surface to have far superior catalytic performance. This promotes the synthesis and evaluation of In2O3 in pure phases with different morphologies. Confirming our theoretical prediction, a novel hexagonal In2O3 nanomaterial with high proportion of the exposed {104} surface exhibits the highest activity and methanol selectivity with high catalytic stability. The synergy between theory and experiment proves highly effective in the rational design and experimental realization of oxide catalysts for industry-relevant reactions.

scholarly journals Computationally aided, entropy-driven synthesis of highly efficient and durable multi-elemental alloy catalysts

2020 ◽  
Vol 6 (11) ◽  
pp. eaaz0510 ◽  
Author(s):  
Yonggang Yao ◽  
Zhenyu Liu ◽  
Pengfei Xie ◽  
Zhennan Huang ◽  
Tangyuan Li ◽  
...  
Keyword(s):  
Density Functional ◽  
Rational Design ◽  
Density Functional Theory Calculations ◽  
Great Promise ◽  
Alloy Formation ◽  
Functional Theory ◽  
Excellent Thermal Stability ◽  
Design And Synthesis ◽  
Highly Efficient ◽  
Computational Strategy

Multi-elemental alloy nanoparticles (MEA-NPs) hold great promise for catalyst discovery in a virtually unlimited compositional space. However, rational and controllable synthesize of these intrinsically complex structures remains a challenge. Here, we report the computationally aided, entropy-driven design and synthesis of highly efficient and durable catalyst MEA-NPs. The computational strategy includes prescreening of millions of compositions, prediction of alloy formation by density functional theory calculations, and examination of structural stability by a hybrid Monte Carlo and molecular dynamics method. Selected compositions can be efficiently and rapidly synthesized at high temperature (e.g., 1500 K, 0.5 s) with excellent thermal stability. We applied these MEA-NPs for catalytic NH3 decomposition and observed outstanding performance due to the synergistic effect of multi-elemental mixing, their small size, and the alloy phase. We anticipate that the computationally aided rational design and rapid synthesis of MEA-NPs are broadly applicable for various catalytic reactions and will accelerate material discovery.

scholarly journals Pd/Pt embedded CN monolayers as efficient catalysts for CO oxidation

2019 ◽  
Vol 21 (46) ◽  
pp. 25743-25748
Author(s):  
Yong-Chao Rao ◽  
Xiang-Mei Duan
Keyword(s):  
Density Functional Theory ◽  
Co Oxidation ◽  
Density Functional ◽  
Carbon Nitride ◽  
Density Functional Theory Calculations ◽  
Catalytic Performance ◽  
Functional Theory ◽  
Spin Polarized ◽  
Planar Carbon

The catalytic performance of Pd/Pt embedded planar carbon nitride for CO oxidation has been investigated via spin-polarized density functional theory calculations.

scholarly journals Influence of Varying Functionalization on the Peroxidase Activity of Nickel(II)–Pyridine Macrocycle Catalysts: Mechanistic Insights from Density Functional Theory

Computation ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 52
Author(s):  
Jerwin Jay E. Taping ◽  
Junie B. Billones ◽  
Voltaire G. Organo
Keyword(s):  
Density Functional Theory ◽  
Proton Transfer ◽  
Density Functional ◽  
Experimental Studies ◽  
Density Functional Theory Calculations ◽  
Catalytic Performance ◽  
Stoichiometric Ratio ◽  
Functional Theory ◽  
Pendant Arm ◽  
Spin Singlet

Nickel(II) complexes of mono-functionalized pyridine-tetraazamacrocycles (PyMACs) are a new class of catalysts that possess promising activity similar to biological peroxidases. Experimental studies with ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), substrate) and H2O2 (oxidant) proposed that hydrogen-bonding and proton-transfer reactions facilitated by their pendant arm were responsible for their catalytic activity. In this work, density functional theory calculations were performed to unravel the influence of pendant arm functionalization on the catalytic performance of Ni(II)–PyMACs. Generated frontier orbitals suggested that Ni(II)–PyMACs activate H2O2 by satisfying two requirements: (1) the deprotonation of H2O2 to form the highly nucleophilic HOO−, and (2) the generation of low-spin, singlet state Ni(II)–PyMACs to allow the binding of HOO−. COSMO solvation-based energies revealed that the O–O Ni(II)–hydroperoxo bond, regardless of pendant arm type, ruptures favorably via heterolysis to produce high-spin (S = 1) [(L)Ni3+–O·]2+ and HO−. Aqueous solvation was found crucial in the stabilization of charged species, thereby favoring the heterolytic process over homolytic. The redox reaction of [(L)Ni3+–O·]2+ with ABTS obeyed a 1:2 stoichiometric ratio, followed by proton transfer to produce the final intermediate. The regeneration of Ni(II)–PyMACs at the final step involved the liberation of HO−, which was highly favorable when protons were readily available or when the pKa of the pendant arm was low.

scholarly journals Ultrahigh sensitive Raman spectroscopy for subnanoscience: Direct observation of tin oxide clusters

2019 ◽  
Vol 5 (12) ◽  
pp. eaax6455 ◽  
Author(s):  
Akiyoshi Kuzume ◽  
Miyu Ozawa ◽  
Yuansen Tang ◽  
Yuki Yamada ◽  
Naoki Haruta ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Tin Oxide ◽  
Density Functional ◽  
Rational Design ◽  
High Sensitivity ◽  
Density Functional Theory Calculations ◽  
Surface Enhanced Raman Spectroscopy ◽  
Atomic Scale ◽  
Practical Applications ◽  
Surface Enhanced Raman

Subnanometric metal clusters exhibit anomalous catalytic activity, suggesting innovative applications as next-generation materials, although identifying and characterizing these subnanomaterials in atomic detail remains a substantial challenge because of the severely weak signal intensity for the conventional analytical methods. Here, we report a subnanosensitive vibrational technique established based on the surface-enhanced Raman spectroscopy, demonstrating the first-ever detailed vibrational characterization of subnanomaterials. Furthermore, combining with density functional theory calculations, we reveal that inherent surface structures of the tin oxide subnanoclusters determine the size-specific spectral and catalytic characteristics of these clusters. The high-sensitivity characterization methodology elaborated here can provide a comprehensive understanding of the chemical and structural natures of subnanomaterials, which facilitate the rational design of subnanomaterials on the atomic scale for practical applications, such as in catalysts, biosensors, and electronics.

Enhanced Catalytic Activity of Carbon Nanotubes for the Oxidation of Cyclohexane by Filling with Fe, Ni, and FeNi alloy Nanowires

2016 ◽  
Vol 69 (6) ◽  
pp. 689 ◽  
Author(s):  
Xixian Yang ◽  
Yuhang Li ◽  
Hao Yu ◽  
Xuchun Gui ◽  
Hongjuan Wang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Catalytic Activity ◽  
Wall Thickness ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Catalytic Performance ◽  
General Strategy ◽  
Thin Walls ◽  
Alloy Nanowires ◽  
Relationship Of

Fe-, Ni-, and alloyed FeNi-filled carbon nanotubes (Fe@CNT, Ni@CNT, and FeNi@CNT) were prepared by a general strategy using a mixture of xylene and dichlorobenzene as carbon source, and ferrocene, nickelocene, and their mixture as catalysts. By tailoring the composition of the carbon precursor, the filling ratio and the wall thickness of metal@CNT could be controlled. For the catalytic oxidation of cyclohexane in liquid phase with molecular oxygen as oxidant, the highest activity was obtained over Fe@CNT synthesized from pure dichlorobenzene. However, Ni filling did not improve the activity of CNTs. The effects of metal filling, wall thickness, and defects on catalytic activity were investigated to determine the structure–activity relationship of the filled CNTs. The enhanced catalytic performance can be attributed to a combined contribution of thin walls of CNTs and confined electron-donating metals, which are favourable to electron transfer on the surfaces of CNTs. The modification of the electronic structure of CNTs upon Fe and Ni fillers insertion was elucidated through density functional theory calculations.

scholarly journals Cation Involvement in Telomestatin Binding to G-Quadruplex DNA

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Frédéric Rosu ◽  
Valérie Gabelica ◽  
Nicolas Smargiasso ◽  
Gabriel Mazzucchelli ◽  
Kazuo Shin-Ya ◽  
...  
Keyword(s):  
Density Functional ◽  
Rational Design ◽  
Density Functional Theory Calculations ◽  
Binding Mode ◽  
Monovalent Cation ◽  
Ammonium Ion ◽  
Mass Measurements ◽  
Functional Theory ◽  
Quadruplex Dna ◽  
G Quadruplex

The binding mode of telomestatin to G-quadruplex DNA has been investigated using electrospray mass spectrometry, by detecting the intact complexes formed in ammonium acetate. The mass measurements show the incorporation of one extra ammonium ion in the telomestatin complexes. Experiments on telomestatin alone also show that the telomestatin alone is able to coordinate cations in a similar way as a crown ether. Finally, density functional theory calculations suggest that in the G-quadruplex-telomestatin complex, potassium or ammonium cations are located between the telomestatin and a G-quartet. This study underlines that monovalent cation coordination capabilities should be integrated in the rational design of G-quadruplex binding ligands.

scholarly journals Ultrafast X-ray diffraction measurements of shock-compressed iron and iron alloys

2020 ◽  
Author(s):  
Andrew Krygier ◽  
Marion Harmand ◽  
Bruno Albertazzi ◽  
Emma McBride ◽  
Kohei Miyanishi ◽  
...  
Keyword(s):  
Phase Stability ◽  
Density Functional ◽  
Solid Phase ◽  
Dynamic Compression ◽  
Density Functional Theory Calculations ◽  
Rapid Onset ◽  
Great Promise ◽  
X Ray Diffraction ◽  
Static Compression ◽  
X Ray

Abstract The extreme pressures achievable with dynamic compression holds great promise for studying planetary interiors. Phase stability of Fe-Si alloys, which are complex to address, is particularly relevant to understanding telluric planetary cores due to the widely varying properties produced by small changes in Si concentration. Here we report the study of phase stability of pure iron and Fe-Si alloys by x-ray diffraction measurements carried out on shocked samples using an x-ray free electron laser (XFEL). Our setup combined with the brilliance of the XFEL allows us to observe the rapid onset of high-pressure solid-solid phase transformation in Fe and Fe-Si8.5wt%; we observe no such evidence in Fe-Si16wt% up to 110 GPa on the nanosecond timescale. Density Functional Theory calculations provide the conceptual framework to rationalize these observations. Taken together our experiments and calculations support recent dynamic compression measurements and shed light on conflicting static compression results. Our work highlights the need to properly consider the differing intrinsic timescales of the static and dynamic experiments when comparing results, and the complementarity of the techniques in assessing phase diagram and transition mechanisms.

scholarly journals A Flexible Electron-blocking Interfacial Shield for Dendrite-free Solid Lithium Metal Batteries

2020 ◽  
Author(s):  
Hanyu Huo ◽  
Jian Gao ◽  
Ning Zhao ◽  
Dongxing Zhang ◽  
Nathaniel Holmes ◽  
...  
Keyword(s):  
Solid State ◽  
Density Functional ◽  
Rational Design ◽  
Electron Tunneling ◽  
Electronic Conductivity ◽  
Lithium Ion ◽  
Density Functional Theory Calculations ◽  
High Electron ◽  
High Electronic Conductivity ◽  
Battery Technology

Abstract Solid-state batteries (SSBs) are considered to be the next-generation lithium-ion battery technology due to their enhanced energy density and safety. However, the high electronic conductivity of solid-state electrolytes (SSEs) leads to Li dendrite nucleation and proliferation. Uneven electric-field distribution resulting from poor interfacial contact can further promote dendritic deposition and lead to rapid short circuiting of SSBs. Herein, a flexible electron-blocking interfacial shield (EBS) is proposed to protect garnet electrolytes from the electronic degradation. The EBS formed by an in-situ substitution reaction can not only increase lithiophilicity but also stabilize the Li volume change, maintaining the integrity of the interface during repeated cycling. Density functional theory calculations show a high electron-tunneling energy barrier from Li metal to the EBS, indicating an excellent capacity for electron-blocking. EBS protected cells exhibit an improved critical current density of 1.2 mA cm-2 and stable cycling for over 400 h at 1 mA cm-2 (1 mAh cm-2) at room temperature. These results demonstrate an effective strategy for the suppression of Li dendrites and present fresh insight into the rational design of the SSE and Li metal interface.

The synergetic effect of aqua ligand and metal site on performance of single-atom catalysts in H2O2 synthesis: a Density Functional Theory Study

2022 ◽  
Author(s):  
Xin-Chen Zhu ◽  
Wei Zhang ◽  
Qian Xia ◽  
Anfu Hu ◽  
Jian Jiang ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Rational Design ◽  
Synergetic Effect ◽  
Density Functional Theory Calculations ◽  
Single Atom ◽  
Density Functional Theory Study ◽  
Functional Theory ◽  
Metal Site ◽  
Coordination Field

To study the effect of coordination field on catalytic property is critical for rational design of outstanding electrocatalyst for H2O2 synthesis. Herein, via density functional theory calculations, we built an...

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