1
|
Brette F, Kourati D, Paris M, Loupias L, Célérier S, Cabioc'h T, Deschamps M, Boucher F, Mauchamp V. Assessing the Surface Chemistry of 2D Transition Metal Carbides (MXenes): A Combined Experimental/Theoretical 13C Solid State NMR Approach. J Am Chem Soc 2023; 145:4003-4014. [PMID: 36779668 DOI: 10.1021/jacs.2c11290] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The surface functionalization of 2D transition metal carbides or nitrides, so-called MXenes, is one of the fundamental levers allowing to deeply modify their physicochemical properties. Beyond new approaches to control this pivotal parameter, the ability to unambiguously assess their surface chemistry is thus key to expand the application fields of this large class of 2D materials. Using a combination of experiments and state of the art density functional theory calculations, we show that the NMR signal of the carbon─the element common to all MXene carbides and corresponding MAX phase precursors─is extremely sensitive to the MXene functionalization, although carbon atoms are not directly bonded to the surface groups. The simulations include the orbital part to the NMR shielding and the contribution from the Knight shift, which is crucial to achieve good correlation with the experimental data, as demonstrated on a set of reference MXene precursors. Starting with the Ti3C2Tx MXene benchmark system, we confirm the high sensitivity of the 13C NMR shift to the exfoliation process. Developing a theoretical protocol to straightforwardly simulate different surface chemistries, we show that the 13C NMR shift variations can be quantitatively related to different surface compositions and number of surface chemistry variants induced by the different etching agents. In addition, we propose that the etching agent affects not only the nature of the surface groups but also their spatial distribution. The direct correlation between surface chemistry and 13C NMR shift is further confirmed on the V2CTx, Mo2CTx, and Nb2CTx MXenes.
Collapse
Affiliation(s)
- Florian Brette
- Université de Poitiers, ISAE-ENSMA, CNRS, PPRIME, 86073 Poitiers, France
- Nantes Université, CNRS, Institut des Matériaux De Nantes Jean Rouxel, IMN, F-44000 Nantes, France
| | - Dani Kourati
- CNRS, CEMHTI UPR3079, Université D'Orléans, 45071 Orléans, France
| | - Michael Paris
- Nantes Université, CNRS, Institut des Matériaux De Nantes Jean Rouxel, IMN, F-44000 Nantes, France
| | - Lola Loupias
- Institut De Chimie Des Milieux Et Matériaux De Poitiers (IC2MP), Université De Poitiers, CNRS, F-86073 Poitiers, France
| | - Stéphane Célérier
- Institut De Chimie Des Milieux Et Matériaux De Poitiers (IC2MP), Université De Poitiers, CNRS, F-86073 Poitiers, France
| | - Thierry Cabioc'h
- Université de Poitiers, ISAE-ENSMA, CNRS, PPRIME, 86073 Poitiers, France
| | | | - Florent Boucher
- Nantes Université, CNRS, Institut des Matériaux De Nantes Jean Rouxel, IMN, F-44000 Nantes, France
| | - Vincent Mauchamp
- Université de Poitiers, ISAE-ENSMA, CNRS, PPRIME, 86073 Poitiers, France
| |
Collapse
|
2
|
DFT investigations of AgMC 7H 10N 2 (M = Cl, Br, and I) metal organic molecules: NMR, optoelectronic, and transport properties. J Mol Model 2022; 28:136. [PMID: 35511304 DOI: 10.1007/s00894-022-05114-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 04/18/2022] [Indexed: 10/18/2022]
Abstract
The full-potential linearized augmented plane wave (FP-LAPW) method was used for the calculation of the structural, nuclear magnetic resonance (NMR), optoelectronic, and thermoelectric properties of AgMC7H10N2 (M = Cl, Br, and I) compounds. The calculated wide band gap of AgMC7H10N2 (M = Cl, Br, and I) metal organic molecules with the density of states approach were 3.32, 3.29, and 3.10 eV, respectively. The NMR parameters are calculated for the Ag, Cl, Br, I, C, N, O, and H elements. It is found that by decreasing bandgap, the isotropic NMR chemical shielding values of Cl, Br, and I elements increase. The strong hybridization of Ag-4d, Cl-3p, Br-4p, and I-5p states are observed at the top of the valence band. The birefringence and anisotropic properties are observed in the optical spectra with high plasmon energies, and the figure of merit, ZT, of 0.98 for AgCl(C7H10N2) compound is found at 300 K. Hence, these compounds are attractive flexible metal organic molecules for optoelectronic and transport applications.
Collapse
|
3
|
Crystal and electronic facet analysis of ultrafine Ni 2P particles by solid-state NMR nanocrystallography. Nat Commun 2021; 12:4334. [PMID: 34267194 PMCID: PMC8282690 DOI: 10.1038/s41467-021-24589-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 06/15/2021] [Indexed: 11/10/2022] Open
Abstract
Structural and morphological control of crystalline nanoparticles is crucial in the field of heterogeneous catalysis and the development of “reaction specific” catalysts. To achieve this, colloidal chemistry methods are combined with ab initio calculations in order to define the reaction parameters, which drive chemical reactions to the desired crystal nucleation and growth path. Key in this procedure is the experimental verification of the predicted crystal facets and their corresponding electronic structure, which in case of nanostructured materials becomes extremely difficult. Here, by employing 31P solid-state nuclear magnetic resonance aided by advanced density functional theory calculations to obtain and assign the Knight shifts, we succeed in determining the crystal and electronic structure of the terminating surfaces of ultrafine Ni2P nanoparticles at atomic scale resolution. Our work highlights the potential of ssNMR nanocrystallography as a unique tool in the emerging field of facet-engineered nanocatalysts. Structural and morphological control of crystalline nanoparticles is crucial in heterogeneous catalysis. Applying DFT-assisted solid-state NMR spectroscopy, we determine the surface crystal and electronic structure of Ni2P nanoparticles, unveiling NMR nanocrystallography as an emerging tool in facet-engineered nanocatalysts.
Collapse
|
4
|
Ludwig M, Hillebrecht H. First-principles calculation of 11B solid-state NMR parameters of boron-rich compounds II: the orthorhombic phases MgB 7 and MgB 12C 2 and the boron modification γ-B 28. Phys Chem Chem Phys 2021; 23:3883-3897. [PMID: 33539490 DOI: 10.1039/d0cp06073a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Based on the work on referencing 11B nuclear magnetic resonance (NMR) spectra for molecular icosahedral boranes and the subsequent transfer to the rhombohedral boron-rich borides of the α-rB12 type, we show that the magic angle spinning (MAS) NMR spectra of boron-rich borides with four or five symmetry-independent boron atoms can also be calculated. The calculations are performed on the level of density functional theory (DFT) using the gauge-including projector-augmented wave (GIPAW) approach. As model compounds o-MgB12C2 and MgB7 are used, for which the experimental spectra could be calculated in excellent agreement with a deviation of 1 to 2 ppm. Based on the calculations, the different B atoms can be assigned to the respective signals, taking into account the quadrupolar coupling constants Cq from computation of the electric field gradient (EFG) with its main axis Vzz. It is shown that due to the specific geometric conditions of icosahedra, the magnitudes of Vzz for the boron atoms involved in exohedral B-B bonds to neighbouring icosahedra depend only on the valence electron density of the bond critical point and the distance. This also applies to the bonds to the interstitial B2 unit in MgB7, but not to bonds to the heteroatom of the C2 dumbbell in o-MgB12C2. Both results are in line with our previous observations for the rhombohedral species (α-rB12; B12X2 with X = P, As, O). Finally, the spectrum of γ-B28 was calculated, whose structure also contains B12 icosahedra and interstitial B2 dumbbells. Here, a very similar bonding situation is found for the icosahedron, but the calculations show that the situation for the B2 unit is clearly different. In general, the only parameter that needs to be varied to fit calculated and measured spectra is the linewidth, as this cannot be calculated. For the cases of o-MgB12C2 and MgB7 signal areas are related to corresponding site multiplicities. A prerequisite for the successful application of the chosen method seems to be the presence of a semiconductor with a sufficiently large band gap, which is the case for the compounds investigated.
Collapse
Affiliation(s)
- Martin Ludwig
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität, Albertstr. 21, 79104 Freiburg, Germany.
| | - Harald Hillebrecht
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität, Albertstr. 21, 79104 Freiburg, Germany.
| |
Collapse
|
5
|
Resolving Dirac electrons with broadband high-resolution NMR. Nat Commun 2020; 11:1285. [PMID: 32152300 PMCID: PMC7062727 DOI: 10.1038/s41467-020-14838-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 02/07/2020] [Indexed: 11/20/2022] Open
Abstract
Detecting the metallic Dirac electronic states on the surface of Topological Insulators (TIs) is critical for the study of important surface quantum properties (SQPs), such as Majorana zero modes, where simultaneous probing of the bulk and edge electron states is required. However, there is a particular shortage of experimental methods, showing at atomic resolution how Dirac electrons extend and interact with the bulk interior of nanoscaled TI systems. Herein, by applying advanced broadband solid-state 125Te nuclear magnetic resonance (NMR) methods on Bi2Te3 nanoplatelets, we succeeded in uncovering the hitherto invisible NMR signals with magnetic shielding that is influenced by the Dirac electrons, and we subsequently showed how the Dirac electrons spread inside the nanoplatelets. In this way, the spin and orbital magnetic susceptibilities induced by the bulk and edge electron states were simultaneously measured at atomic scale resolution, providing a pertinent experimental approach in the study of SQPs. The detection of topological states is restricted to limited experimental tools. Here, the authors apply broadband solid-state 125Te nuclear magnetic resonance on Bi2Te3 nanoplatelets uncovering signals distinguishing edge Dirac electrons and bulk electrons.
Collapse
|
6
|
Blaha P, Schwarz K, Tran F, Laskowski R, Madsen GKH, Marks LD. WIEN2k: An APW+lo program for calculating the properties of solids. J Chem Phys 2020; 152:074101. [DOI: 10.1063/1.5143061] [Citation(s) in RCA: 585] [Impact Index Per Article: 146.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Peter Blaha
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Karlheinz Schwarz
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Fabien Tran
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Robert Laskowski
- Institute of High Performance Computing, A*STAR, 1 Fusionopolis Way, #16-16, Connexis 138632, Singapore
| | - Georg K. H. Madsen
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Laurence D. Marks
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
| |
Collapse
|
7
|
Benndorf C, Eckert H, Janka O. Structural Characterization of Intermetallic Compounds by 27Al Solid State NMR Spectroscopy. Acc Chem Res 2017; 50:1459-1467. [PMID: 28590712 DOI: 10.1021/acs.accounts.7b00153] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intermetallic compounds are of broad interest for solid state chemists, condensed matter physicists, and material scientists due to their intriguing crystal chemistry, their physical properties, and their potential applications, ranging from lab curiosities to everyday objects. To characterize and understand the properties of new compounds and novel materials, the availability of structural information, particularly single-crystal X-ray diffraction data, is a mandatory prerequisite. Especially when it comes to the formation of compounds with deficient or mixed site occupancies, superstructures, or representatives crystallizing in other, thus far unknown structure types, a complementary method for structural analysis is of great value. Solid state nuclear magnetic resonance spectroscopy has been a valuable tool in many areas of chemistry, being an element-selective, site-specific, and inherently quantitative tool for detailed structural characterization. Magic-angle spinning conditions eliminate or reduce the effect of anisotropic interactions in the solid state, producing high-resolution spectra. Until recently, 27Al NMR studies of intermetallic aluminum compounds have been relatively sparse and mostly limited to binary systems. In this Account, we will summarize the current state of the art of high-resolution 27Al NMR in intermetallic compounds focusing on recent research efforts in our laboratories and the interpretation of NMR parameters in terms of the structural details of the compounds investigated. Besides theoretical aspects of 27Al NMR spectroscopy, short paragraphs on experimental details and the crystal chemistry of the discussed compounds are given. In the main part of this Account, we focus on three key aspects: (i) crystal structure validation, (ii) structural disorder and mixed site occupancies, and (iii) the electronic structure, all of which can be investigated by spectroscopic means. For the first part, we have chosen the ternary equiatomic compounds CaAuAl (TiNiSi type), BaAuAl (LaIrSi type), and Ba3Pt4Al4 (own type). Structural disorder and mixed site occupancies have been probed in the ScTAl series (T = Cr, Ru, Ag, Re) crystallizing in the TiNiSi, HfRhSn, and MgZn2-type structures. Also Na2Au3Al and the Heusler compounds, Sc(T0.5T'0.5)2Al (T = T' = Ni, Pd, Pt, Cu, Ag, Au), have been used for structure validation purposes, based on the number and signal area ratios of the resonances observed and on the comparison between experimental and theoretically calculated nuclear electric quadrupolar interaction parameters. Electronic structure information available from 27Al magnetic shielding will be discussed based on experimental data obtained for the RET5Al2 series (RE = Y, Lu; T = Pd, Pt), the extended RE10TAl3 series (RE = Y, Lu; T = Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt), and the ordered Heusler compounds ScT2Al (T = Ni, Pd, Pt, Cu, Ag, Au).
Collapse
Affiliation(s)
- Christopher Benndorf
- Institut
für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
- Institut
für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
- Institut
für Mineralogie, Kristallographie und Materialwissenschaften, Universität Leipzig, Scharnhorststraße 20, 04275 Leipzig, Germany
| | - Hellmut Eckert
- Institut
für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
- Instituto
de Física de São Carlos, Universidade de São Paulo, São
Carlos, SP 13566-590, Brazil
| | - Oliver Janka
- Institut
für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 28/30, 48149 Münster, Germany
- Institut
für Chemie, Carl von Ossietzky Universität Oldenburg, Carl-von-Ossietzky-Straße
9-11, 26129 Oldenburg, Germany
| |
Collapse
|
8
|
Benndorf C, Stein S, Heletta L, Kersting M, Eckert H, Pöttgen R. A25Mg,89Y and115In solid state MAS NMR study of YT2X and Y(T0.5T′0.5)2X (T/T′ = Pd, Ag, Au; X = Mg, In) Heusler phases. Dalton Trans 2017; 46:250-259. [DOI: 10.1039/c6dt04097g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Yttrium–transition metal–magnesium (indium) Heusler phases were synthesized from the elements in sealed niobium ampoules in a high-frequency furnace or by arc-melting, respectively.
Collapse
Affiliation(s)
- Christopher Benndorf
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
- Institut für Physikalische Chemie
| | - Sebastian Stein
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Lukas Heletta
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Marcel Kersting
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Hellmut Eckert
- Institut für Physikalische Chemie
- Universität Münster
- D-48149 Münster
- Germany
- Institute of Physics in Sao Carlos
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| |
Collapse
|
9
|
Sundholm D, Fliegl H, Berger RJ. Calculations of magnetically induced current densities: theory and applications. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2016. [DOI: 10.1002/wcms.1270] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Dage Sundholm
- Department of Chemistry; University of Helsinki; Helsinki Finland
| | - Heike Fliegl
- Centre for Theoretical and Computational Chemistry (CTCC), Department of Chemistry; University of Oslo; Oslo Norway
| | - Raphael J.F. Berger
- Paris-Lodron University of Salzburg; Chemistry of Materials; Salzburg Austria
| |
Collapse
|