id stringlengths 24 24 | idx int64 0 402 | paragraph stringlengths 106 17.2k |
|---|---|---|
655ecdfecf8b3c3cd7e9e56c | 0 | Solid fast-ion conductors represent a distinct class of ion-conducting materials characterized by the diffusion of a specific type of atom through the interstitial spaces within a solid lattice while other atoms remain stationary in their crystal sites. This unique behavior allows liquid-like conduction of the particul... |
655ecdfecf8b3c3cd7e9e56c | 1 | ASSBs, in particular, are considered promising candidates for high-energy-density batteries, addressing the growing demand in the electric vehicle market as conventional lithium-ion batteries (LIBs) approach the theoretical limit . Solid oxide fuel cells (SOFCs), another important application, can also benefit from the... |
655ecdfecf8b3c3cd7e9e56c | 2 | Conducting ions in a solid phase faces various challenges due to the dense packing of atoms within the crystal structure, which limits the availability of space for ionic diffusion. As a result, the ionic conductivity in solids is generally low. However, achieving ionic conductivities above 1 mS cm -1 is typically cruc... |
655ecdfecf8b3c3cd7e9e56c | 3 | Additionally, maintaining effective connectivity between the electrode and electrolyte poses another significant challenge. The development of solid-fast ion conductors has witnessed notable progress in synthesizing new materials (Fig. ) and addressing these challenges. Researchers have explored a diverse range of mobi... |
655ecdfecf8b3c3cd7e9e56c | 4 | For the purpose of comparison, Fig. provides an overview of the ionic conductivities (low to high conductivity range in (b)) and the activation energy of key ionic conductors along with their structures. The chronological order of their discovery is also displayed in Fig. . Notably, Yttria (Y 2 O 3 ) stabilized zirconi... |
655ecdfecf8b3c3cd7e9e56c | 5 | Over the past few years, researchers have made significant progress in synthesizing high ion-conducting materials for solid-state devices. Despite decades of research, only a limited number of materials demonstrate both high RT conductivity (σ RT > 100 mS cm -1 ) and a low activation energy (E a close to 0.1 eV). In ad... |
655ecdfecf8b3c3cd7e9e56c | 6 | X-ray and neutron diffraction are particularly useful for determining the crystal structure, which are crucial for understanding ionic conduction. Quasielastic neutron scattering (QENS) measurements help in understanding atomic orientation, particularly in cases where isolated anions exhibit significant reorientation. ... |
655ecdfecf8b3c3cd7e9e56c | 7 | This review is structured as follows: We briefly highlight a few fundamental equations related to ionic conductivity and the major factors responsible for controlling ionic conductivity in section II. Then, we categorized the materials based on the framework structures in section III. In each class of materials, we ana... |
655ecdfecf8b3c3cd7e9e56c | 8 | In liquid electrolytes, the transport of lithium ions involves their movement within the solvent medium. In contrast, in crystalline solids, the conduction of lithium ions requires passing through periodic BN points, creating an energy barrier between two local energy minima. The conductivity of ions in liquid electrol... |
655ecdfecf8b3c3cd7e9e56c | 9 | Fast molecular or ion exchange is necessary for fast ion conduction in liquid electrolytes. In contrast, in crystalline solids, the diffusion of mobile species, such as lithium ions, encounters periodic BN points offered by immobile framework species. These points define energetic barriers that separate two local minim... |
655ecdfecf8b3c3cd7e9e56c | 10 | The diffusion process is examined by calculating cations and anions' mean square displacement (MSD). In a real system, the local energy landscape usually determines the hop of mobile atoms. However, for simplicity, we start with a random-walk model , where the cross term becomes zero and the self-diffusion coefficient,... |
655ecdfecf8b3c3cd7e9e56c | 11 | where R n is the total displacement of a moving ion in n steps, t n is the duration to complete n steps of ion displacement, a is the hopping distance between two neighboring sites or free path, ν is the jump frequency of successful jumps, and b is a geometry factor of 2, 4, or 6 for one-, two-, or three-dimensional di... |
655ecdfecf8b3c3cd7e9e56c | 12 | where N m denotes the number of target ions in the system for diffusion calculation, ∆⃗ r i = ⃗ r i (t + t ′ ) -⃗ r i (t) is the displacement of the i th ion; t is the time origin, while t ′ is the time difference, and the angular bracket, the average over several points in time, for statistical equal weight at each po... |
655ecdfecf8b3c3cd7e9e56c | 13 | where ν 0 is the attempt frequency, or the number of attempted jumps within unit time, and includes both successful jumps that can lead to macroscopic diffusion and unsuccessful ones. ∆G m is the Gibbs free energy of activation, k B is the Boltzmann constant, T is the absolute temperature, ∆S m is the activation entrop... |
655ecdfecf8b3c3cd7e9e56c | 14 | Once the system is in the diffusive region, the MSD graph follows a straight-line behavior, and the diffusion coefficient, D r , can be calculated from the slope of the straight line against the time difference. It is worth noting that if there is a correlated diffusion, the self-diffusion differs from the collective d... |
655ecdfecf8b3c3cd7e9e56c | 15 | Essentially, the H R is a ratio between the average MSD of all the mobile atoms and the MSD of the center of mass of all the mobile atoms (denominator ). As the center of mass of the target ions is equivalent to a single particle behavior, it is a fluctuating quantity. Thus, in practice, several independent runs are co... |
655ecdfecf8b3c3cd7e9e56c | 16 | The pre-exponential component encompasses multiple factors, including the exponential dependence of entropy. Even a slight alteration in any of these factors, particularly within the exponential part, can substantially impact ion conduction. Consequently, this phenomenon explains why materials with similar structures d... |
655ecdfecf8b3c3cd7e9e56c | 17 | Anionic Rotation: Anion rotation is a phenomenon that occurs in some ionic compounds, where the anions can rotate around their own axes, resulting in reorientation. It can be a partial or full rotation, depending on the materials. This can affect the ionic conductivity of the material, as the rotation can create or dis... |
655ecdfecf8b3c3cd7e9e56c | 18 | where rj (t), and rj (t + t ′ ) denote the unit vectors connecting from the center of mass of anions to an edge atom in the same anion at time t and t + t ′ , respectively. N e is the number of edge atoms in the anion. This function typically shows an exponential decay (≈ e -λt ′ ) within a short time with a decay rate... |
655ecdfecf8b3c3cd7e9e56c | 19 | Layered oxide materials are a class of solid fast-ion conductors that have a distinctive structure consisting of mobile cations sandwiched between rigid framework layers. These materials exhibit high ionic conductivity, especially for alkali metal ions, and have potential applications in energy storage and electrochemi... |
655ecdfecf8b3c3cd7e9e56c | 20 | Notably, β-alumina also demonstrates fast ion conduction for divalent and even trivalent cation species . This characteristic expands its potential applications and highlights its versatility as a solid-state ionic conductor. The ability of β-alumina to facilitate the rapid conduction of alkali metal ions is attributed... |
655ecdfecf8b3c3cd7e9e56c | 21 | Moreover, synthesizing these materials is straightforward, allowing researchers to obtain high-quality samples for study and characterization. The general formula of β-alumina is M 2 O.xAl 2 O 3 (where M = Li, Na, Ag, K, and Rb) . This material consists of two distinct subgroups: β ′ and β ′′ , each characterized by a ... |
655ecdfecf8b3c3cd7e9e56c | 22 | Within the conduction layer, three different cationic sites exist: anti-Beevers-Ross (aBR), Beevers-Ross (BR), and mid-Oxygen (mO) (Fig. )) . The sites are different based on the local oxygen environment, such as BR is formed by three top and three bottom oxygens, and aBR is formed by two oxygens (one top and one botto... |
655ecdfecf8b3c3cd7e9e56c | 23 | These MD simulations revealed the importance of non-stoichiometric composition in enhancing cationic diffusion and observed a transition from low-temperature hopping transport to a higher-temperature liquid-like transport . Further MD studies by Thomas and Zendejas focused on Na-β ′′ -alumina and provided additional at... |
655ecdfecf8b3c3cd7e9e56c | 24 | In β ′ -alumina, the dominant conduction mechanism involves the migration of oxygen ions (O 2-) through the crystal lattice, utilizing oxygen vacancies as diffusion paths. In β ′′ -alumina, the conduction mechanism revolves around the migration of sodium ions (Na + ) through the crystal lattice, facilitated by the pres... |
655ecdfecf8b3c3cd7e9e56c | 25 | Although empirical fitting potentials by Walker and Catlow have been successful in MD studies, accurately describing lattice vibrations has remained a challenge. Kamishima et al. developed a set of potential parameters by fitting phonon vibrational modes, providing a more accurate representation of lattice vibrations i... |
655ecdfecf8b3c3cd7e9e56c | 26 | Layered oxide solids have attracted considerable attention as potential materials for Sodium-ion batteries since Na x CoO 2 was first introduced as a cathode material. Typical layered honeycomb oxides consist of alkali or coinage metal atoms sandwiched between slabs made exclusively of transition metal and chalcogen (o... |
655ecdfecf8b3c3cd7e9e56c | 27 | Despite several improvements in materials synthesis, the fundamental understanding was lacking. Taking a broader perspective, MD simulations of Na 2 Ni 2 TeO 6 aim to understand the physics of sodium ion transport in honeycomb layered oxide materials, which have potential applications in energy storage and electrochemi... |
655ecdfecf8b3c3cd7e9e56c | 28 | The presence of cationic vacancies and configurational entropy was found to play a crucial role in the ion migration mechanism. The conductivity can be tuned by varying the cationic concentrations among the inter-layer on the conduction layer, as shown in Fig. ) . A general characteristic of honeycomb layered material ... |
655ecdfecf8b3c3cd7e9e56c | 29 | Conventionally, materials in this category are characterized by a single conduction layer. However, their work has yielded a particularly intriguing material, namely Ag 6 M 2 TeO 6 (where M can represent Ni, Mg, or other transition metal atoms), which exhibits a distinctive structure featuring bi-layers of Ag atoms wit... |
655ecdfecf8b3c3cd7e9e56c | 30 | In order to explore the distinctive properties of these bilayer-type honeycomb layered oxides, a preliminary MD simulation was conducted by Sau using a previously reported force field, with interaction parameters similar to those of Na 2 Ni 2 TeO 6 . During this simulation, the polyhedral layers were held fixed at thei... |
655ecdfecf8b3c3cd7e9e56c | 31 | In the case of Ag 6 M 2 TeO 6 , it was observed that the inter-layer distance is relatively substantial, approximately 6 Å, in contrast to Na 2 Ni 2 TeO 6 , which exhibits an inter-layer distance of approximately 3 Å. Consequently, mobile cations within the bilayer have a tendency to approach the oxygen layer, resultin... |
655ecdfecf8b3c3cd7e9e56c | 32 | These materials face several formidable obstacles, including but not limited to low ionic conductivity under ambient conditions, restricted diffusion along the c-direction owing to non-penetrable rigid framework layers, structural instability stemming from larger inter-layer separations, and volumetric alterations duri... |
655ecdfecf8b3c3cd7e9e56c | 33 | Polyhedral Connecting Framework Structures are another class of materials that exhibit a three-dimensional network of polyhedra. These polyhedra, which can be of various shapes, such as tetrahedra and octahedra, are connected at their corners or edges to form a continuous framework. This structure creates channels or c... |
655ecdfecf8b3c3cd7e9e56c | 34 | Solid electrolytes with covalently bonded, interconnected polyhedral structures form another class of materials. These materials usually exhibit high Debye temperatures, thermal and chemical stability, and melting points, offering high operating temperatures for practical applications. Lithium Garnet type materials, wi... |
655ecdfecf8b3c3cd7e9e56c | 35 | Lithium conducting garnets, Li 3 Ln 3 Te 2 O 12 (Ln = Y, Pr, Nd, Sm-Lu), typically contain 5-7 formula units where lithium ions occupy at tetrahedral and octahedral sites, as depicted in Fig. . Since the original work by Murugan et al. , it has attracted numerous experimental and theoretical studies. It is observed tha... |
655ecdfecf8b3c3cd7e9e56c | 36 | The high conducting cubic garnet Li 7 La 3 Zr 2 O 12 (LLZO) was reported by Murgun et al. , and later on, the tetragonal phase was detected at a lower temperature by Awaka et al. . The cubic phase shows two orders of magnitude higher conductivity than the tetragonal phase . Several computational studies have been condu... |
655ecdfecf8b3c3cd7e9e56c | 37 | The low-temperature tetragonal phase exhibits synchronous collective Li + ion hopping, causing a high activation energy barrier. In cubic LLZO, the Li + finds unoccupied sites, resulting in uncorrelated Li + motion that costs less activation energy. Hu et al. , and others reported that higher valent ion (Al 3+ ) substi... |
655ecdfecf8b3c3cd7e9e56c | 38 | the aliovalent substitutions (e.g., Ta 5+ ) at Zr sites also enhance the ionic conductivity . An order of magnitude of conductivity is enhanced from Li 5 La 3 Ta 2 O 12 to Li 6 BaLa 2 Ta 2 O 12 where the Li ions are occupied in tetrahedral as well as octahedral sites . Thus, garnet-type materials are found to be promis... |
655ecdfecf8b3c3cd7e9e56c | 39 | Significant research efforts have been dedicated to enhancing the ionic conductivity in Lithium Super Ionic Conductors (LISICONs). In 1978, Hong identified poor ionic conductivity (10 -7 S cm -1 at ambient temperature) in Li 14 Zn(GeO 4 ) 4 and related materials such as Li 4 GeO 4 -LiVO 4 , Li 2+2x Zn 1-x GeO4, Li 2 O-... |
655ecdfecf8b3c3cd7e9e56c | 40 | LGPS has since garnered substantial attention, both for elucidating its underlying mechanisms and addressing cost-related concerns. The LGPS material features (Ge 0.5 P 0.5 )S 4 tetrahedra and PS 4 tetrahedra with space group P4 2 /nmc, as illustrated in Fig. (d). Li + ions occupy tetrahedral and octahedral sites, allo... |
655ecdfecf8b3c3cd7e9e56c | 41 | Despite its high Li + ion conductivity, a portion of Li + ions in LGPS remains localized at octahedral sites, not contributing to Li + ion diffusion. This material exhibits highly anisotropic Li + conduction through partially occupied tetrahedral Li-sites with a low activation energy of 0.24 eV. However, the atomic ori... |
655ecdfecf8b3c3cd7e9e56c | 42 | After the discovery of β-alumina, there was a strong belief in existing similar types of materials with three-dimensional ion conduction . The expectation became a reality when Hong and Goodenough et al. synthesized NASICON (an acronym for Na SuperIonic CONductor), marking a significant breakthrough in the pursuit of f... |
655ecdfecf8b3c3cd7e9e56c | 43 | NASICON exhibits promising characteristics, including high three-dimensional ionic conductivity, as well as thermal and chemical stability. It is a class of 3D materials with remarkable RT ionic conductivity (≈ 10 -3 S cm -1 ), often exceeding that of liquid electrolytes at high temperatures. Furthermore, NASICONs offe... |
655ecdfecf8b3c3cd7e9e56c | 44 | Later on, several new sites (A2, A3, or mid-A, etc., where A = Li or Na) were introduced by modifying the framework. Detailed site environments are here. The A1 is situated between two TiO 6 octahedra along the crystallographic c-axis, while A2 connects two A1 sites. The A1 is surrounded by oxygen octahedra (A 1 O 6 ) ... |
655ecdfecf8b3c3cd7e9e56c | 45 | Kumar et al. developed a comprehensive interionic potential that accurately predicts the lattice constants and ionic conductivity of NZPO as a function of composition (x = 2) , as displayed in Fig. ). The study revealed that, at this composition, the number of Na + ions and available vacancies is exactly doubled, indic... |
655ecdfecf8b3c3cd7e9e56c | 46 | 5(h)), which has a smaller size compared to Zr, resulting in a smaller BN for the smaller cation (Li + ). Further studies have been conducted to understand the correlation between the framework skeleton and cationic conductivity in this series. In general, ionic diffusion increases with a larger BN formed by the NASICO... |
655ecdfecf8b3c3cd7e9e56c | 47 | The activation energy also decreases systematically with an increasing BN radius (Fig. ). Pramanik et al. performed a systematic MD study to understand atomistic insights into such systematic behavior . An interesting dynamic behavior of framework BN (the BN opens up while passing the cation through its center) was rev... |
655ecdfecf8b3c3cd7e9e56c | 48 | Mouahid et al. ( ) conducted a comprehensive analysis of the structure and electrical properties of Na 1+x Ti 2-x Al x (PO 4 ) 3 materials within the range of 0.6< x <0.9, which belong to the NASICON type. This investigation employed a combination of X-ray diffraction, Rietveld analysis, and impedance spectroscopy tech... |
655ecdfecf8b3c3cd7e9e56c | 49 | 5 , where it becomes evident that larger-sized atoms tend to occupy the more stable Na1 site. Furthermore, the authors proposed that this phenomenon leads to a mixed alkali effect, which in turn reduces the ionic conductivity and elevates the activation energy of the (Li/Na) 1+x series when compared to pure sodium anal... |
655ecdfecf8b3c3cd7e9e56c | 50 | In the pursuit of enhancing ionic conductivity, researchers have explored a fascinating approach involving the substitution of divalent elements within the NASICON framework, leading to the creation of cationic vacancies. A compound of particular interest in this regard is Ba x/2 Li 1-x Ti 2 (PO 4 ) 3 , where the range... |
655ecdfecf8b3c3cd7e9e56c | 51 | Motivated by this phenomenon, Sau et al. conducted MD (MD) study on Ba x/2 Li 1-x Ti 2 (PO 4 ) 3 , exploring compositions ranging from 0.0 < x < 0.83 to unravel the atomistic origins of enhanced cationic diffusion . Their investigations revealed that below the composition of x = 0.67, an abundance of cationic vacancies... |
655ecdfecf8b3c3cd7e9e56c | 52 | This structural feature facilitates facile anion rotation, associated with large cell volume change (Fig. )), making these materials unique. The ordered (O)-disordered (D) phase transition in these materials can be qualitatively elucidated by considering the Gibbs free energy difference between the high-temperature (hi... |
655ecdfecf8b3c3cd7e9e56c | 53 | This free energy difference comprises three key terms: internal energy (∆E), entropy (-T ∆S), and volume (p∆V ). Notably, the internal energy remains relatively constant throughout the phase transition, while the volume term opposes the stabilization of the D phase due to ∆V > 0. Consequently, within the domain of clus... |
655ecdfecf8b3c3cd7e9e56c | 54 | In the field of solid electrolytes for all-solid-state batteries (ASSBs), the comparison between β-alumina and NASICONs has been a subject of scientific exploration. However, it wasn't until 2007 that hydride materials, which have been used for hydrogen storage since 1969, were recognized for their potential as fast io... |
655ecdfecf8b3c3cd7e9e56c | 55 | In light of the promising characteristics exhibited by hydrides, it is imperative to address several formidable challenges before realizing their practical utility, with a notable concern being their relatively deficient ionic conductivity at RT . Taking lithium borohydride (LiBH 4 ) as an illustrative example, it is e... |
655ecdfecf8b3c3cd7e9e56c | 56 | This underscores the pivotal role played by phase transitions within this class of materials. Consequently, it is paramount to gain a comprehensive understanding of the intricacies surrounding phase transition phenomena, encompassing the underlying factors and origins. This improved conductivity in LiBH 4 arises due to... |
655ecdfecf8b3c3cd7e9e56c | 57 | By tuning the size and shape of the anions and cations, one can manipulate the diffusion pathways and barriers for cationic diffusion. This leads to the formation of novel anions, such as M 2 B n H n , where (M = Li, Na, and n = 10, 12), that have wider interstitial spaces and thus facilitate cation diffusion. These an... |
655ecdfecf8b3c3cd7e9e56c | 58 | The story of ionic conductivity in Li 2 B 12 H 12 and its analogs is a tale of O and D, of cations and anions, of rotations and vibrations . However, the fast and complex motion of the anions also poses a challenge in determining their lattice sites and rotational modes, resulting, in most cases, undetermined structure... |
655ecdfecf8b3c3cd7e9e56c | 59 | The study argued that the facile anion reorientations and other low-frequency thermal vibrations lead to fluctuations in the local potential that enhance cation mobility by creating a local driving force for hopping. Sau et al. also shed light on Li 2 B 12 H 12 using force-field-based MD simulations. They developed a f... |
655ecdfecf8b3c3cd7e9e56c | 60 | The intriguing behavior of LiCB 11 H 12 as a solid electrolyte was further explored by Sau et al. , using force-field-based MD simulations. The study revealed underlying mechanisms such as cation-cation and cation-anion correlations. From the comparative study with Li 2 B 12 H 12 , a sharp phase transition from O to D ... |
655ecdfecf8b3c3cd7e9e56c | 61 | These vacancies increased the number of carriers available for ion transport, resulting in a remarkable improvement of lithium-ion conductivity by three orders of magnitude (2.0 × 10 -5 S cm -1 at 30 • C). Interestingly, the activation energy of the ion conduction remained almost unchanged, suggesting that the atom def... |
655ecdfecf8b3c3cd7e9e56c | 62 | Tang et al. Through their comprehensive investigation, it was found that the optimal composition occurred at x = 0.7, showcasing the highest ionic conductivity. It was attributed to the structural frustration caused by the mismatched sizes of the anions, which flattened the energy landscape for anion rotation, resultin... |
655ecdfecf8b3c3cd7e9e56c | 63 | The intricate interplay between anions and cations in solid electrolytes plays a vital role in determining their functional properties. In the case of (Li/Na)CB 11 H 12 , an intriguing solid electrolyte, the interaction between anions and cations can be further manipulated by introducing an additional carbon atom, resu... |
655ecdfecf8b3c3cd7e9e56c | 64 | As previously highlighted, a comprehensive understanding of the factors influencing the diminishment of rotational activation energy (E r a ) is imperative for stabilizing the high-conductivity phase in complex hydrides at RT. In this regard, we have identified cell expansion as a pivotal factor in modulating anion-cat... |
655ecdfecf8b3c3cd7e9e56c | 65 | This includes reducing the cation density or decreasing the valency of the anionic species. Such strategic adjustments yield a discernible reduction in the rotational activation energy (E r a ), as illustrated in Fig. ). This multifaceted approach ultimately leads to a significant decrease in the critical T tran , as e... |
655ecdfecf8b3c3cd7e9e56c | 66 | This scientific journey begins with the pioneering work of Higashi et al., reporting remarkable Mg 2+ ion conductivity properties of Mg(BH 4 )(NH 2 )(demonstrated a conductivity of 10 -6 S cm -1 at 150 • C) . The conduction mechanism involved the movement of magnesium ions within tetrahedral structures formed by comple... |
655ecdfecf8b3c3cd7e9e56c | 67 | Importantly, Mg(BH 4 )(NH 2 ) was the first magnesium ion conductor where Mg stripping and plating behavior were confirmed. Building on this breakthrough, subsequent investigations explored the electrochemical properties of all-solid-state batteries utilizing Mg(BH 4 )(NH 2 ) as a solid electrolyte, sulfide-based posit... |
655ecdfecf8b3c3cd7e9e56c | 68 | In recently, the introduction of neutral molecules has emerged as a promising strategy to enhance conductivity in complex hydride-based magnesium ion conductors. Such as introducing ether can also improve ionic conductivity for closo-type magnesium boron cluster salt (10 -3 mS cm -1 at 45 • C), reported by Mizuno et al... |
655ecdfecf8b3c3cd7e9e56c | 69 | [165] using metadynamics simulation and correlation analysis between activation energy and other physical properties. The metadynamics simulations study found an increase in the activation energy of cation migration with a lower coordination number of H 2 O. In addition, in the correlation analysis, the activation ener... |
655ecdfecf8b3c3cd7e9e56c | 70 | In pursuit of developing efficient solid electrolytes for advanced battery technologies, significant research has been dedicated to thiophosphate-based materials. Among these, lithium argyrodites have emerged as a highly researched class, with promising conductive properties reaching up to 24 mS cm -1 . However, it is ... |
655ecdfecf8b3c3cd7e9e56c | 71 | Arising from the general formula Li 7 PS 6 , argyrodite materials display a transition from a normal to a superionic phase from orthorhombic to a cubic phase. However, their RT ionic conductivity remains relatively low, with values around 1.6 ×10 -6 S cm -1 . The high-conducting phase can be stabilized by introducing c... |
655ecdfecf8b3c3cd7e9e56c | 72 | Among the single halide argyrodites, Li 6 PS 5 Cl exhibits the highest ionic conductivity at ambient temperature, approximately 10 -3 S cm -1 , followed by Li 6 PS 5 Br with around 10 -4 S cm -1 , while Li 6 PS 5 I displays the lowest ionic conductivity, approximately 10 -6 S cm -1 , as illustrated in Fig. ). The origi... |
655ecdfecf8b3c3cd7e9e56c | 73 | A comprehensive investigation into bulk conductivity within the argyrodite material Li 6 PS 5 Cl has been conducted, employing a combination of 7 Li nuclear magnetic resonance (NMR) experiments and DFT-based MD simulations by Yu et al. . This study has shed light on two distinct lithium-ion diffusion mechanisms within ... |
655ecdfecf8b3c3cd7e9e56c | 74 | Notably, Hanghofer et al. have put forth an alternative perspective based on their research, offering new insights into the diffusion mechanisms within argyrodite materials, especially in cases where X represents Cl, Br, or I. Their investigation employed 31 P magic angle spinning (MAS) NMR to probe the rotational move... |
655ecdfecf8b3c3cd7e9e56c | 75 | These complementary studies provide valuable insights into the intricate mechanisms governing ion diffusion within argyrodite materials. They underscore the significance of considering both local and long-range diffusion processes in comprehending the ionic conductivity properties of these materials. Continuing efforts... |
655ecdfecf8b3c3cd7e9e56c | 76 | reported the partial substitution of lithium (Li) sites with Al 3+ /B 3+ in Li 6 PS 5 X (X = Cl and Br), and Li 5.4 Al 0.2 PS 5 Br exhibited an increased ionic conductivity of 2.4 × 10 -3 S cm -1 at RT . In another study, tellurium (Te) doping in Li 6.25 PTe 0.125 S 5.125 Cl 0.75 resulted in a relatively high ionic con... |
655ecdfecf8b3c3cd7e9e56c | 77 | In the pursuit of high-performance solid-state batteries, the presence of an electrochemically stable solid electrolyte possessing an exceptional ionic conductivity exceeding 10 mS cm -1 is paramount. This remarkable attribute can be attained through the utilization of sulfide-based Na + solid ionic conductors . The cl... |
655ecdfecf8b3c3cd7e9e56c | 78 | Mobile M -ions occupy the tetrahedral voids within this cubic structure, which belongs to the space group I43m, as illustrated in Fig. . They typically undergo a transition from a normal to a superionic phase, specifically from a tetragonal to a cubic structure. Interestingly, the cubic phase remains stable at RT for c... |
655ecdfecf8b3c3cd7e9e56c | 79 | A distinct shift in the pair distribution function, as depicted in Fig. , indicated a phase transition. In the high-conductivity phase, a ring-like local density of Na + ions emerged, and their strong connectivity reflects long-range diffusion. The distribution of sulfur (S) atoms, as shown in Fig. , provided further e... |
655ecdfecf8b3c3cd7e9e56c | 80 | Recent research by Bo et al. has focused on enhancing sodium ion conductivity in Na 3 PS 4 and Na 3 PSe 4 by conducting combined experimental and ab initio MD studies . They found nearly identical energy barriers for Na + diffusion in both Se and S substituted systems. Their study proposed that introducing a 2.1% Na io... |
655ecdfecf8b3c3cd7e9e56c | 81 | investigated Na 3 PS 4 using ab initio MD simulations and discovered that Na + ions primarily migrate through interstitial Na1 (6b) and Na2 (12d) sites, with a preference for the Na1 sites. Aliovalent substitution, such as Na 3+x M x P 1-x S 4 with M = Si, Ge, and Sn, significantly enhances sodium ion conductivity at R... |
655ecdfecf8b3c3cd7e9e56c | 82 | Maximum Na + conductivity of 1.66 × 10 -3 S cm -1 is achieved with a Si/P ratio of 6:94, closely matching reported experimental conductivity values . Aliovalent substitution is a commonly employed strategy for enhancing ionic conductivity, as demonstrated by Maus et al. . Their work resulted in remarkable Na + ion cond... |
655ecdfecf8b3c3cd7e9e56c | 83 | 3-ions and exhibits pseudo-rotation at RT. The study also found the existence of pseudo-rotation in other complex transition metal hydrides containing OsH within this class of materials, Li 6 NbH 11 deserves attention, as it features Li + ions exhibiting several meta-stable sites, which implies a lower hopping barrier ... |
655ecdfecf8b3c3cd7e9e56c | 84 | These materials encounter challenges such as low ionic conductivity at RT and high sensitivity to ambient conditions. The substantial anionic rotational disorder represents a formidable barrier to gaining structural insights during the high-conductivity phase. Elucidating the intricacies of structure-property relations... |
655ecdfecf8b3c3cd7e9e56c | 85 | The development of solid ion conductors has primarily relied on the ion conduction mechanism described by Equation , where ion movement occurs through hopping within a crystalline lattice . Numerous structural families have demonstrated reasonably high Li-ion conductivity at RT, with the ability to vary Li-ion conducti... |
655ecdfecf8b3c3cd7e9e56c | 86 | Coordination Number: Early studies found that the conditions that are responsible for high ionic conductivity are realized with monovalent cation in a four-(tetrahedral) or three-coordinated configuration with the anions . Recent studies have expanded this idea to link the high ionic conductivity observed in lithium su... |
655ecdfecf8b3c3cd7e9e56c | 87 | Several theoretical and experimental studies (DFT calculations and neutron scattering experiments) have been performed recently to understand the phonon modes that are coupled most strongly with ionic conductivity and assess the role of anharmonicity. It has been ascertained that the anharmonicity inherent in the phono... |
655ecdfecf8b3c3cd7e9e56c | 88 | Dimensionality: Three-dimensional (3D) diffusion pathways are crucial for achieving high σ, as they provide a lower possibility of blocking the ion conduction path. Structures that possess 3D diffusion pathways often exhibit a correlation with high σ, while lower dimensionalities often result in reduced ionic transport... |
655ecdfecf8b3c3cd7e9e56c | 89 | This change in the coordination environment creates a structural "bottleneck" for the diffusion process. It has been established that this BN is closely linked to the activation barriers and conductivities observed in ionic conductors . Structural modifications arising from substitutions and strains can significantly i... |
655ecdfecf8b3c3cd7e9e56c | 90 | This rationale explains why sulfide ionic conductors often exhibit low activation barriers and higher ionic conductivity compared to more ionic oxides . Several notable examples exist where the modification of the anion framework and the alteration of the strength of local bonding interactions exert a discernible influ... |
655ecdfecf8b3c3cd7e9e56c | 91 | where σ 0 = H R q 2 a 2 N c(1-c)ν0 exp( ∆Sm For cations, the key attributes include a uniform coordination environment, the presence of three-dimensional ion-conducting channels, a high concentration of mobile ions, and a vacancy-rich structure. Additionally, for anions, the ideal features encompass a highly frustrated... |
655ecdfecf8b3c3cd7e9e56c | 92 | (σ) is directly proportional to the square of the carrier charge. Consequently, augmenting the charge, as seen in the case of divalent conducting carriers, is more advantageous than relying on monovalent carriers. However, it is essential to acknowledge that higher valency is concurrently associated with stronger inter... |
655ecdfecf8b3c3cd7e9e56c | 93 | Another pivotal factor to consider is the jump distance, denoted as a. A larger value of a is conducive to achieving fast ion conduction; nevertheless, it can potentially lead to structural instability. Similarly, a high cationic concentration is directly proportional to enhanced ionic conductivity, but an excessive nu... |
655ecdfecf8b3c3cd7e9e56c | 94 | Additionally, a higher attempt frequency favors fast ion conduction. It is important to note that the dimension factor is found in the denominator of the conductivity equation. Therefore, lower dimensions are favorable for achieving higher conductivity values. However, this preference for lower dimensions must be caref... |
655ecdfecf8b3c3cd7e9e56c | 95 | In this section, we put forth a set of potential characteristics for an ideal fast ion conductor based on our comprehensive understanding of various material classes and the underlying theoretical advancements in fast ion conduction. In order to explore these features, we have classified the materials from both the cat... |
655ecdfecf8b3c3cd7e9e56c | 96 | In this review, we focused on the major classes of fast ion conductors, such as layered oxides, polyhedral connecting frameworks, and cluster anion-type materials, and a comprehensive exploration of their structural and dynamical properties, mechanisms governing ion transportation, and strategies for enhancing ionic co... |
655ecdfecf8b3c3cd7e9e56c | 97 | VII. Acknowledgments K.S. thanks the JSPS International Fellowship. K.S. also thanks Prof. Padma Kumar Padmanabhan for his useful discussions. This work was supported by JSPS KAKENHI Grant-in-Aid for Scientific Research on Innovative Areas "Hydrogenomics", No. JP18H05513 and JSPS Fellowship grant (21F21345). This work ... |
657552c45bc9fcb5c97b17c9 | 0 | First synthesized in 1963 by van Tamelen, Dewar benzene consists of two fused strained cyclobutenes. Suitably substituted derivatives are promising as energy storage materials due to the reversibility of the Dewar benzene formation. For example, hexafluorobenzene is selectively and in high yield photoisomerized to its ... |
657552c45bc9fcb5c97b17c9 | 1 | isomers may provide an avenue to new classes of highly functionalized polyolefins via ring-opening metathesis polymerization (ROMP). Although relatively less studied, ROMP of strained cyclobutenes is well established and typically accomplished using Grubbs 2 nd (G2), Grubbs 3 rd (G3), or Hoveyda-Grubbs 2 nd (HG2) gener... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.