Topochemical Bottom-Up Synthesis of 2D- and 3D-Sodium Iron

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Topochemical Bottom-up Synthesis of 2Dand 3D-Sodium Iron Fluoride Frameworks Utsav Kumar Dey, Nabadyuti Barman, Subham Ghosh, Shreya Sarkar, Sebastian C. Peter, and Premkumar Senguttuvan Chem. Mater., Just Accepted Manuscript • DOI: 10.1021/acs.chemmater.8b04010 • Publication Date (Web): 02 Jan 2019 Downloaded from http://pubs.acs.org on January 2, 2019

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Chemistry of Materials

Topochemical Bottom-up Synthesis of 2D- and 3D-Sodium Iron Fluoride Frameworks Utsav Kumar Dey,†, a Nabadyuti Barman,†, a Subham Ghosh, a Shreya Sarkar, a Sebastian C. Peter a,c and Premkumar Senguttuvan.a,b,c,*. a

New Chemistry Unit, bInternational Centre for Materials Science and cSchool of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore-560064, India.

ABSTRACT: A new topochemical bottom-up approach is demonstrated for the first time to synthesize two (2D)- and three dimensional (3D)-sodium iron fluoride frameworks (NaFeF4 and Na2Fe2F7 respectively) through the incorporation of a “structure-stabilizing” agent (i.e. sodium fluoride) into a one-dimensional (1D)-FeF3·3H2O host structure. While the conversion of 1D to 2D framework is enabled by the simultaneous topochemical reactions (dehydration, ion exchange and condensation), the transformation of 2D to 3D structure involves a minor structural rearrangement induced by reductive deintercalation of iron and fluoride ions. All through the structural transformations, the 1D trans-connected chains of FeF6 octahedra originating from FeF3·3H2O host lattice, are retained. The as-prepared 3D-Na2Fe2F7 cathode has shown promising electrochemical properties with the highest intercalation voltage (~3.25 V vs. Na+/Na0) and reversible capacities above 50 mAh/g for 30 cycles.

The ability to predict the structure, composition and formation mechanism of non-molecular extended solids remains as the fundamental research interest of solid-state chemists to synthesize new inorganic materials.1 Although crystal chemistry reasoning (such as oxidation state, coordination number, bond length etc.) and computer modelling2 studies could be utilized to design new extended structures, the choice of chemical routes plays a pivotal role to achieve the targeted materials.3 Traditionally, ceramic routes have been employed to prepare inorganic solids wherein high temperature and long annealing duration are required to drive diffusion-limited solid-state reactions. However, its “heat and beat” reaction conditions often result in the formation of thermodynamically stable structures and compositions. The low temperature routes, on the other hand, have manifold utilities in terms of cost, atom economy, energy efficiency and environmental foot-print4 and give access to metastable phases.5,6 One such approach, topochemical synthesis, offers us a great control over the formation of products as the direct rationale between them and their respective precursors could be drawn with reference to structural connectivity and crystallographic orientation.7-11 So far, two major topochemical strategies were pursued; the first one had involved synthesis of thermodynamically stable phases at high temperatures, followed by use of low temperature soft-chemical approaches such as ion exchange, intercalation/de-intercalation, dehydration and condensation to convert low-dimensional solids to higher ones, but mostly they were performed in sequential steps.12-15 The second one was based on dimensional reduction formalism, wherein higher dimensional structures were reduced to lower ones through the incorporation of dimensional reducing agents into the parent frameworks.16 Herein, we report a new topochemical methodology, i.e. a bottom-up approach, to convert one dimensional (1D)-FeF3.3H2O

(hereafter denoted as IF) precursor structure to higher dimensional iron fluoride framework through incorporation of a “structure-stabilizing” agent, i.e. sodium fluoride (NaF) into it. The addition of NaF knits the isolated 1D chains of FeF6 present in IF to make corrugated [FeF4] layers of two dimensional (2D)NaFeF4 structure which are stabilized by interlayer sodium ions. Further, reductive deintercalation involving iron and fluoride ions of 2D-framework induces minor structural rearrangement to form three dimensional (3D)-Na2Fe2F7 structure. The as-synthesized Na2Fe2F7 cathode showed reversible capacities above 50 mAh/g for 30 cycles with an average intercalation voltage of 3.25 V vs. Na+/Na0, the highest value reported for iron fluorides in NIBs. In a typical synthesis, NaF and IF (1:1 stoichiometric ratio) were introduced in tetraethylene glycol (TEG) in an autoclave at room temperature and subsequently, the mixture was heated in an oil bath with constant stirring at different temperatures (refer Experimental Section in Supporting Information (SI)). Figure 1a shows the XRD patterns of products synthesized at different temperatures and time durations. When the mixture was heated to 180°C for 6 to 24 h, XRD patterns of the corresponding products remained unchanged and all of them could be indexed with monoclinic layered-NaFeF4 crystal structure (space group P21/c).17 Note the reflection at 2θ = 14.7⁰ (denoted by an asterisk) represents a secondary phase, which will be discussed in the following section. Figure 1b depicts the Rietveld refinement of XRD pattern of 2D-NaFeF4 obtained from 24 h dwelling. The corresponding lattice parameters and atomic coordinates are listed in Table 1 and S1 (refer to SI) respectively. NaFeF4 structure is built by corrugated layers of [FeF4] stacking along [100]2D axis while sodium ions occupy the interstitial sites between layers (Figure 1b). Note that the subscript used in the crystallographic direction denotes the corresponding crystal structures. The distorted (zigzag) environment of FeF6 units

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gives a Bond Valence Summation (BVS) of +3.05 for Fe ions (Table S2, SI). The Mössbauer spectroscopic data (Figure S1(a) and Table S3, SI) obtained for NaFeF4 shows symmetric band splitting, thus indicating the presence of only Fe3+ ions. Furthermore, as the reaction temperature was raised to 230°C, and kept for 6 h, the XRD pattern of the corresponding product (Figure 1a) showed a new set of reflections, along with the peaks of the NaFeF4 phase, thus indicating the formation of a new phase. When the dwelling time was extended to 24 h, the layered phase was completely vanished and only the new phase was retained. The XRD pattern of the newly formed phase was refined based on a starting model of weberite-Na2M2+Mʹ3+F7 (M=Ni and Mg, Mʹ= Fe) with Imma space group (Figure 1b).18,19 The refinement gave Rwp value of 1.68 and the corresponding cell parameters and atomic sites are listed in Table 1 and S4 (refer to SI) respectively.

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The refined structure of Na2Fe2F7 (Figure 1b) consists of two independent iron ions with different oxidation states, i.e. Fe2+ and Fe3+, occupying 4c and 4b Wyckoff sites, respectively. The calculated bond lengths and BVS are given in Table S5, SI. Both iron ions are surrounded by six fluoride ions and the average bond distances of Fe2+F6 and Fe3+F6 octahedra are found to be 2.00 Å and 1.95 Å, respectively. Two trans-connected chains of Fe2+F6 octahedra running along [100]3D direction are corner shared to four isolated Fe3+F6 units through axial fluoride ions, forming three-dimensional network of [Fe2F7]. In this 3D arrangement, sodium ions occupy two different Wyckoff sites (4a and 4d), each of which are coordinated with 8 fluoride anions (refer to the Figure S2, SI). Na(1)F8 units with two different Na−F bond lengths show edge shared distorted square prism environment and leads to the formation of Na-ion channels along [100]3D direction, whereas Na(2)F8 units are in hexagonal bipyramidal environment with three different Na-F bond lengths giving rise to the Na-channel along [010]3D direction. There is one more Na-ion channel present in [111]3D direction, consisting of alternating Na(1) and Na(2) ions. The BVS values of the Fe ions in 4c and 4b sites are found to be +2.35 and +2.93 respectively (Table S5, SI). The higher BVS value for Fe2+ could be due to the distorted environment of Fe2+(1)F6 octahedra. In accordance with the BVS calculation, the fitted Mössbauer data (Figure S1(b), SI) obtained for the weberite phase demonstrates one doublet peak due to quadrupole splitting of unsymmetrical Fe2+(1)F6 units and another doublet due to the presence of symmetric electronic transition for Fe3+ ions. The quantification of Fe2+ and Fe3+ ions along with the isomeric shift obtained from Mössbauer spectra listed in Table S3. Table 1. Calculated lattice parameters and weighted profile R- factors (Rwp) for NaFeF4 and Na2Fe2F7 phases. Space Group

Figure 1. (a) Powder X-Ray diffraction patterns of different sodium iron fluoride products obtained at various reaction temperatures and time-durations. (b) Rietveld refinement of the room temperature XRD patterns of the as-synthesized NaFeF4 and Na2Fe2F7 and their corresponding crystal structures. The blue and red octahedra correspond to Fe3+F6 and Fe2+F6 units respectively. The yellow balls represent sodium ions present in the 4e and 4a sites of NaFeF4 and Na2Fe2F7 respectively, whereas the green balls denote the sodium ions sit in the 4d sites of Na2Fe2F7. Fluoride ions are shown in grey color.

NaFeF4

P21/c

Na2Fe2F7

Imma

Lattice parameters a =7.93233(2)Å b = 5.35691(8) Å c =7.53821(12)Å a = 7.3567(10) Å b = 10.4920(4) Å c = 7.4180(9) Å

α = 90° β = 102.06° γ = 90° α = 90° β = 90° γ = 90°

Rwp

1.38

1.68

The possible mechanism of structural transformation from 1DIF to 2D-NaFeF4 framework is discussed in Figure 2. It is interesting to compare the structural topologies between 1D-IF and 2D-NaFeF4; both contain trans-connected 1D chains of FeF2(H2O)4 and FeF6 octahedra along their [001] directions, respectively. The isolated linear 1D chains in the precursor is stabilized by hydrogen bonded water molecules.20 In order to convert 1D to 2D network, two out of four F-/OH- groups (denoted as a, aʹ, b and bʹ in Figure 2a) in FeF2(H2O)4 units situated at F(2)/O(2) sites are required to be cis-connected along the [010]1D direction. Consequently, the 1D chains become zigzag along [001]2D direction and their coalescence leads to the formation of corrugated layers of [FeF4] along [010]2D direction in the NaFeF4 structure. Surprisingly, one can notice that the sodium ions take the same position of H+ ions of H2O molecular channels situated at the center of the cavity in the IF host along [001]1D axis (Figure 2b), thus forming zig-zag sodium ion layers in between [FeF4] layers in the 2D structure.


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Chemistry of Materials

Figure 2. Topochemical transformation from 1D-FeF3.3H2O to 2DNaFeF4 via simultaneous ion-exchange between Na+/F- and H+/OH, condensation of F-/OH- and dehydration reactions. The trans-connected FeF6 octahedra (blue) along [001]1D in precursor is retained in the 2D lattice. (a) The knitting occurs in the [010] 1D direction transforming the 1D chains to 2D corrugated layers. (b) Site selective ion exchange between the interstitial water molecules (red) and the Na+-ions (yellow) and the formation of zigzag sodium ion channels along the [010]2D direction.

Based on the aforementioned discussion, it is clear that the transformation of 1D to 2D framework necessitates removal of water molecules, ion-exchange between Na+/F- and H+/OHgroups and condensation of F-/OH- groups in the precursor, as summarized in the following equation: 𝑁𝑎𝐹 + 𝐹𝑒𝐹 · 3𝐻 𝑂 → 𝑁𝑎𝐹𝑒𝐹 + 3𝐻 𝑂 .............(I) To grasp more insights into the underlying reaction mechanisms responsible for this structural transformation, we have undertaken FTIR and SEM studies on the IF precursor and the 2D product. FTIR measurements have shown no sign of OHgroups in the as-synthesized NaFeF4 in comparison with the precursor (Figure S3, SI), thus signifying complete ion-exchange between OH- and F- groups. The SEM image (Figure S4, SI) of the 2D product has revealed the presence of micron sized rod like particles and to our surprise, no sign of porosity was noticed. This observation directly contradicts the previous finding on the stabilization of HTB-FeF3·0.33H2O from the same IF precursor through dehydration and structural densification which has yielded porous agglomerates of nanoparticles.20 Therefore, it is obvious to conclude that concurrent dehydration and ion-exchange reactions have to occur in order to avoid structural densification and yield compact micron sized particles. Yet, the most intriguing question still remains is how the reaction proceeds between NaF and micron sized particles of IF precursor. We believe that the dissolved Na+ and F- ions (at least partially in TEG at elevated temperatures) would have been transported through the water channels (ca. cavity size of ~4.6 Å as shown in Figure S5, SI) present along the [001]1D-direction of the IF structure. Once they reach their corresponding reactions sites in the host IF lattice simultaneous ion-exchange and condensation reactions occur in parallel to the dehydration, which results in the formation of 2D-NaFeF4. Let us turn our attention towards the structural transformation of 2D-NaFeF4 to 3D-Na2Fe2F7. The structures of NaFeF4 and

Na2Fe2F7 phases contain the 1D chains of FeF6 octahedra running along [001]2D and [100]3D axis, respectively (Figure 3a and e). The striking difference between them is the connectivity of the 1D chains, i.e. they are cis-corner connected (through F(2) vertices) in the 2D structure, whereas the 3D framework is built by corner sharing of 1D chains with isolated FeF6 units. To enable this structural transformation, one half of the 1D chains of the corrugated layers of NaFeF4 structure (shown in red color in Figure 3b and hereafter denoted as red 1D chains) are preserved, while the other half (shown in blue color in Figure 3b and hereafter denoted as blue 1D chains) are broken into isolated FeF6 units to pillar the red 1D chains. Considering the stoichiometry and oxidation states of the elements present in both iron fluoride phases, this transformation requires half of the Fe3+ ions present in NaFeF4 to be reduced to Fe2+ ions, as confirmed by the Mössbauer analysis, along with a possible elimination of fluoride ions. Thus, it is expected that the reductive deintercalation of iron and fluoride ions in the 2D structure has triggered the structural rearrangement, which could be tentatively explained as follows.

Figure 3. Topochemical transformation of (a) 2D-NaFeF4 to (e) 3D-Na2Fe2F7. (b) A part of the corrugated layer of the 2D structure (indicated by a rectangle box in figure (a)) is shown in a different crystallographic direction. The blue 1D chains cleaves at all trans Fe-F(1)-Fe and every other Fe-F(2)-Fe positions and the corresponding blue octahedra alternatively rotate clockwise or counter clockwise and coalesce with the next red octahedra of the red 1D chains giving rise to the structural motifs of red 1D chains with isolated blue octahedra as shown in figure (c). (d) The blue octahedra of the structural motifs condense via F(3) and F(4) corners of 1D FeF6 chains from the adjacent layer of 2D-NaFeF4 (indicated by a red circle in figure a and c respectively) to make three dimensional framework of [Fe2F7].

During the transformation, all the trans-connected Fe-F(1)-Fe bonds of the blue 1D chains and every other Fe-F(2)-Fe bonds between the red and blue 1D chains are broken (Figure 3b), thus leaving the blue FeF6 octahedra to be connected through only one corner (i.e. the remaining Fe-F(2)-Fe bonds) to the red 1D chains, as indicated in Figure 3c. This process leads to complete loss of direct connectivity between two red 1D chains present in the same layer of NaFeF4 and further, the blue octahedra rotate clockwise or counter-clockwise and coalesce with the next red octahedra in the same red 1D chain through F(2) corners, producing structural motifs of red 1D chains with isolated blue octahedra as shown in Figure 3c. Such bond breaking phenom-



ena is expected to destabilize the structure, wherein the blue octahedra in the as-produced structural motifs attach to the FeF6 octahedra (encircled in red in Figure 3a and 3c) of 1D red chain from the adjacent layer through F(3) and F(4) vertices to make the diagonal connectivity (red-blue-red) which results in the formation of three dimensional [Fe2F7] framework (Figure 3e). Accordingly, the two layers of sodium ions in the 2D structure are also rearranged; the sodium ions (shown in green color), which sit adjacent to the as-retained 1D red chains, are pushed in between them, and form a layer (denoted as A in Figure 3e) comprising of alternating chains of Na(1)-F8 and Fe(1)F6 units along the [100]3D direction. The other layer of sodium ions in the 2D structure (shown in yellow color) also migrate in clockwise and counter-clockwise to occupy the interstitial sites in between blue octahedra, thus forming the chains of edge shared Fe(2)F6 octahedra and Na(2)F8 hexagonal bi-pyramids in the [100]3D direction. Further, these chains are connected through corners to make a layer (denoted as B in Figure 4e) of alternating Fe(2)F6 and Na(2)F8 units. These A and B layers are alternatively stacked along the [010]3D direction in the Na2Fe2F7 structure. Overall, these structural rearrangements increase and decrease the distance between the red 1D chains present in the same and alternative layers of 3D framework (with respect to the 2D structure) to ~ 7.42 Å and ~ 5.24 Å respectively.

Figure 4. (a) Potential vs. capacity plots, (b) Discharge capacity and Coulombic efficiency vs Cycle number plots of 3D-Na2Fe2F7 electrode cycled at C/10 in between 2.6-3.8 V vs. Na+/Na0.

To probe the origin of the reductive deintercalation, which has triggered the structural transformation, we have conducted the following control experiments. The 2D-NaFeF4 samples were annealed at 230 °C under nitrogen flow for different dwelling time. The XRD patterns of the corresponding samples were unchanged (Figure S6, SI), which was further supported by the evidence of negligible mass loss from Thermogravimetric Analysis (Figure S7, SI). Further, the as-synthesized NaFeF4 phase was suspended into TEG in the autoclave and subsequently heated to 230 ⁰C for 12 h. The XRD pattern (Figure S8, SI) of the harvested product was well matched with as-prepared Na2Fe2F7. Therefore, we can conclude that TEG plays a vital role on the reductive deintercalation involving Fe3+ to Fe2+ ions along with fluorine elimination, as observed for the other class of compounds.21,22 The cracks on micron sized cuboid Na2Fe2F7 particles (Figure S4, SI) may have formed during the structural rearrangement and is also expected to facilitate the ingression of TEG inside the particles. From the view point of high intercalation voltages demonstrated for other iron fluoride cathodes in NIBs, 23,24 we further attempted to explore the sodium intercalation/de-intercalation properties of 2D-NaFeF4 and 3D-NaFe2F7 frameworks. Their respective electrodes were cycled against sodium metal at C/10 in between 2.6-3.8 V vs. Na+/Na0. The NaFeF4 phase did not show any significant capacity, which may be due to inactive

Fe3+/Fe4+ redox center (Figure S9, SI). On the other hand, during the first cycle, the 3D-NaFe2F7 phase exhibited sloping voltage profiles with a reversible capacity of 58 mAh/g (Figure 4a). The corresponding redox activity could be tentatively ascribed to the operation of Fe3+/Fe2+ couple and the average intercalation voltage (~3.25 V vs. Na+/Na0) is found to be much higher than the values reported for other iron fluoride cathodes for NIBs.23-27 Remarkably, the polarization between charge and discharge processes (Figure S10, SI) was found to be ~ 150 mV, thus indicating facile intercalation and deintercalation of sodium ions into 3D framework. On the subsequent cycles, the 3D framework has maintained capacities over 50 mAh/g with Coulombic efficiencies of >99% (Figure 4b). To sum up, we have demonstrated the first example of a new topochemical bottom-up approach to synthesize higher dimensional sodium iron fluorides through the inclusion of the structure-stabilizing agent (NaF) into 1D-IF host lattice. Simultaneous topochemical reactions have facilitated the merging of the 1D chains during the formation of 2D-NaFeF4, whilst the reductive deintercalation of iron and fluorine has triggered the structural rearrangement to form the 3D-Na2Fe2F7.The as-prepared weberite-Na2Fe2F7 cathode has shown the highest insertion voltage with an excellent cycling stability among other iron fluorides that are reported so far. Whilst NaFeF4 and monoclinicNa2Fe2F7 phases were synthesized previously at high temperatures,17, 28 the present approach has not only tailored these materials at relatively low temperatures, but also has harvested a new polymorph of Na2Fe2F7 in orthorhombic structure, which has been achieved by directing the structural connectivity rooting from precursor lattice. In the light of topochemical routes utilized to produce battery cathodes,29-31 we expect this bottomup approach to open new avenues in topochemical synthesis to tailor new higher dimensional alkali ion bearing cathodes based on the low dimensional precursor structures.

ASSOCIATED CONTENT Supporting Information Experimental details, Mössbauer, FTIR, FESEM, TGA, additional electrochemical and XRD data, Na-ion channels in the weberite phase, cavity size in the 1D precursor, tables for the structural details and Mössbauer analysis. The Supporting Information is available free of charge on the ACS Publication website.

AUTHOR INFORMATION Corresponding Author * [email protected]

Author Contributions †

U. K. Dey and N. Barman contributed equally to this work.

Notes The authors declare no competing financial interest.

ACKNOWLEDGMENT This work was supported by SERB (ECR-2017/00068) and Sheikh Saqr Laboratory, JNCASR.

REFERENCES


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Chemistry of Materials (1) DiSalvo, F. J. Solid-State Chemistry: A A Rediscovered Chemical Frontier. Science 1990, 247, 649-655. (2) Catlow C. R. A.; Bell, R. G.; Gale, J. D. Computer modelling as a technique in materials chemistry. J. Mater. Chem., 1994, 4, 781-792. (3) Rao, C. N. R., Gopalakrishnan, J. Synthesis of complex metal oxides by novel routes. Acc. Chem. Res. 1987, 20, 228-235. (4) Tarascon, J. M.; Recham, N.; Armand, M.; Chotard, J. N.; Barpanda, P.; Walker, W.; Dupont, L. Hunting for Better LiBased Electrode Materials via Low Temperature Inorganic Synthesis. Chem. Mater. 2010, 22, 724-739. (5) Chernova, N. A.; Roppolo, M.; Dillon, A. C.; Whittingham, M. S. Layered vanadium and molybdenum oxides: batteries and electrochromics. J. Mater. Chem. 2009, 19, 2526-2552. (6) Chirayil, T.; Zavalij, P. Y.; Whittingham, M. S. Hydrothermal Synthesis of Vanadium Oxides. Chem. Mater. 1998, 10, 2629-2640. (7) Gopalakrishnan, J. Chimie Douce Approaches to the Synthesis of Metastable Oxide Materials. Chem. Mater. 1995, 7, 1265-1275. (8) Schaak, R. E.; Mallouk, T. E. Perovskites by Design: A Toolbox of Solid-State Reactions. Chem. Mater. 2002, 14, 1455-1471. (9) SanjayaRanmohotti, K. G.; Josepha, E.; Choi, J.; Zhang, J.; Wiley, J. B. Topochemical Manipulation of Perovskites: Low-Temperature Reaction Strategies for Directing Structure and Properties. Adv. Mater. 2011, 23, 442-460. (10) Parija, A.; Waetzig, G. R.; Andrews, J. L.; Banerjee, S. Traversing Energy Landscapes Away from Equilibrium: Strategies for Accessing and Utilizing Metastable Phase Space. J. Phys. Chem. C 2018, 122, 25709-25728. (11) Xiao, X.; Wang, H.; Urbankowski, P.; Gogotsi, Y. Topochemical synthesis of 2D materials. Chem. Soc. Rev. 2018, 47, 8744-8765. (12) Feist, T. P.; Davies, P. K. The Soft Chemical Synthesis of TiO2 (B) from Layered Titanates. J. Solid State Chem. 1992, 101, 275-295. (13) Gopalakrishnan, J.; Bhat, V. A2La2Ti3O10 (A= K or Rb; Ln = La or Rare Earth): A New Series of Layered Perovskites Exhibiting Ion Exchange. Inorg. Chem. 1987, 26, 42994301. (14) Schaak, R. E.; Mallouk, T. E. Topochemical Synthesis of Three-Dimensional Perovskites from Lamellar Precursors. J. Am. Chem. Soc. 2000, 122, 2798-2803. (15) Montasserasadi, D.; Mohanty, D.; Huq, A.; Heroux, L.; Payzant, E. A.; Wiley, J. B. Topochemical Synthesis of Alkali-Metal Hydroxide Layers within Double- and TripleLayered Perovskites. Inorg. Chem. 2014, 53, 1773-1778. (16) Tulsky, E. G.; Long, J. R. Dimensional Reduction: A Practical Formalism for Manipulating Solid Structures. Chem. Mater. 2001, 13, 1149-1166. (17) Dance, J. M.; Sabatier, R.; Ménil, F.; Wintenberger, M.; Cousseins, J. C.; Le Flem, G.; Tressaud, A. ETUDE D’UN NOUVEAU TYPE FLUORURE ANTIFERROMAGNETIQUE A CARACTERE BIDIMENSIONNEL: NaFeF4. Solid State Commun. 1976, 19, 1059-1065.

(18) Cai, L.; Nino, J. C. Complex ceramic structures. I. Weberites. ActaCryst. 2009, B65, 269-290.

(19) Laligant, Y.; Calage, Y.; Heger, G.; Pannetier, J.; Ferey, G.

(20) (21)

(22) (23)

(24)

(25)

(26)

(27) (28)

(29)

(30)

(31)

J. Ordered Magnetic Frustration VII. Na2NiFeF7: Reexamination of Its Crystal Structure in the True Space Group after Corrections from Renninger Effect and Refinement of Its Frustrated Magnetic Structure at 4.2 and 55K. Solid State Chem. 1989, 78, 66-77. Li, C.; Yin, C.; Mu, X.; Maier, J. Top-Down Synthesis of Open Framework Fluoride for Lithium and Sodium Batteries. Chem. Mater. 2013, 25, 962-969. Moorhead-Rosenberg, Z; Harrison, K. L; Turner, T; Manthiram, A. A Rapid Microwave-Assisted Solvothermal Approach to Lower-Valent Transition Metal Oxides. Inorg. Chem. 2013, 52, 13087-13093. Gutierrez, A.; Manthiram, A. Microwave-Assisted Solvothermal Synthesis of Spinel AV2O4 (M= Mg, Mn, Fe, and Co). Inorg. Chem. 2014, 53, 8570-8576. Yi, T.; Chen, W.; Cheng, L.; Bayliss, R. D.; Lin, F.; Plews, M. R.; Nordlund, D.; Doeff, M. M.; Persson, K. A.; Cabana, J. Investigating the Intercalation Chemistry of Alkali Ions in Fluoride Perovskites. Chem Mater. 2017, 29, 1561-1568. Zhang, R.; Wang X.; Wang X.; Liu, M.; Wei, S.; Wang, Y.; Hu, H. Iron Fluoride Packaged into 3D Order Mesoporous Carbons as High-Performance Sodium-Ion Battery Cathode Material. J. Electrochem. Soc. 2018, 165, A89-A96. Han, Y.; Hu, J.; Yin, C.; Zhang, Y.; Xie, J.; Yin, D.; Li, C. Iron-based fluorides of tetragonal tungsten bronze structure as potential cathodes for Na-ion batteries. J. Mater. Chem. A 2016, 4, 7382-7389. Li, C.; Yin, C.; Gu, L.; Dinnebier, R. E.; Mu, X.; Van Aken, P. A.; Maier, J. An FeF3·0.5H2O Polytype: A Microporous Framework Compound with Intersecting Tunnels for Li and Na Batteries J. Am. Chem. Soc. 2013, 135, 11425-11428. Cao, D; Yin, C; Shi, D; Fu, Z; Zhang, J; Li, C. Cubic Perovskite Fluoride as Open Framework Cathode for Na-Ion Batteries. Adv. Funct. Mater. 2017, 27, 1701130, 1-9. Yakubovich, O; Urusov, V; Massa, W; Frenzen, G; Babel, D. Z. Structure of Na2Fe2F7 and Structural Relations in the Family of Weberites Na2MIIMIIIF7. Anorg. Allg. Chem. 1993, 619, 1909-1919. Recham, N.; Chotard, J. N.; Dupont, L.; Delacourt, C.; Walker, W.; Armand, M.; Tarascon, J. M. A 3.6V lithiumbased fluorosulphate insertion positive electrode for lithiumion batteries. Nat. Mater. 2010, 9, 68-74. Lee, K. T.; Ramesh, T. N.; Nan, F.; Botton, G.; Nazar, L. F. Topochemical Synthesis of Sodium Metal Phosphate Olivines for Sodium-Ion Batteries. Chem. Mater. 2011, 23, 3593-3600. Parija, A. Liang, Y.; Andrews, J. L.; De Jesus, L. R.; Prendergast, D.; Banerjee, S. Topochemically De-Intercalated Phases of V2O5 as Cathode Materials for Multivalent Intercalation Batteries: A First-Principles Evaluation. Chem. Mater. 2016, 28, 5611-5620.



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Topochemical Bottom-Up Synthesis of 2D- and 3D-Sodium Iron

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