Organic Intercalation Research Articles

Fabrication of red-emitting perovskite LEDs by stabilizing their octahedral structure.

Light-emitting diodes (LEDs) based on metal halide perovskites (PeLEDs) with high colour quality and facile solution processing are promising candidates for full-colour and high-definition displays1-4. Despite the great success achieved in green PeLEDs with lead bromide perovskites5, it is still challenging to realize pure-red (620-650 nm) LEDs using iodine-based counterparts, as they are constrained by the low intrinsic bandgap6. Here we report efficient and colour-stable PeLEDs across the entire pure-red region, with a peak external quantum efficiency reaching 28.7% at 638 nm, enabled by incorporating a double-end anchored ligand molecule into pure-iodine perovskites. We demonstrate that a key function of the organic intercalating cation is to stabilize the lead iodine octahedron through coordination with exposed lead ions and enhanced hydrogen bonding with iodine. The molecule synergistically facilitates spectral modulation, promotes charge transfer between perovskite quantum wells and reduces iodine migration under electrical bias. We realize continuously tunable emission wavelengths for iodine-based perovskite films with suppressed energy loss due to the decrease in bond energy of lead iodine in ionic perovskites as the bandgap increases. Importantly, the resultant devices show outstanding spectral stability and a half-lifetime of more than 7,600 min at an initial luminance of 100 cd m-2.

Strain engineering of Bi2S3 microspheres via organic intercalation enabled high performance sodium storage

Conversion or alloying-type layered metal chalcogenides, which hold great promise as anodes for sodium storage, encounter a significant challenge of volume expansion due to the accumulation of inner strain during the charge–discharge process. This issue leads to severe stress concentration and necessitates urgent attention in terms of dispersing the distribution of inner strain through advanced strain engineering techniques. In this study, we have successfully fabricated Bi2S3-TTAB microspheres composed of Bi2S3 nanorods intercalated with tetradecyltrimethylammonium bromide (TTAB). By periodically inserting the soft TTAB into the interlayer of Bi2S3, we effectively isolate and confine the Bi2S3 layers while simultaneously expanding the interlamellar spacing. This innovative approach disperses and alleviates the inner strain of Bi2S3 at an atomic level, thereby ensuring electrode stability. As a competitive conversion-alloying-type anode for sodium-ion batteries, the Bi2S3-TTAB microspheres demonstrate remarkable performance in terms of high rate capacities and cycle stability (208.4 mAh g−1 at 15 A g−1; 4910 cycles at 10 A g−1 with 87.8 % capacity retention). This exceptional Na-ion storage capability enables the utilization of Bi2S3-TTAB combined with active carbon as an advanced sodium ion capacitor that demonstrates impressive energy and power densities (144.0 Wh kg−1 and 5.0 kW kg−1).

The surface and interlayer modification of montmorillonite and its potential application for thermal energy storage

Phase change materials (PCMs) could take full advantage of clean and renewable energy, because of their ability to convert and store various energy. However, due to the leakage and low heat storage capacity, the large-scale commercial application of PCMs is seriously limited. In this work, natural montmorillonite (MMT) was modified by organic amine coupling agent that was assembled into the interlayer of MMT. The energy storage performance and the stability of composite PCMs were significantly improved by using a novel frame of MMT encapsulated Paraffin (PA). The MMT-KH550-HAc/PA composite PCMs prepared by organic intercalation provides suitable pore structure and hydrophilicity to encapsulate more PA, resulting in the highest latent heat capacity (150 J/g) that is significantly increased by 144.1% from 60 J/g. Meanwhile, the energy storage stability of MMT-KH550-HAc/PA is also improved, and the latent heat of phase change is reduced by 3.2% after 100 cycles. The present MMT-KH550-HAc/PA has remarkable latent heat capacity and energy storage stability, which can be potentially applied to the solar water heaters.

Prominent Nonlinear Optical Absorption in SnS2‐Based Hybrid Inorganic–Organic Superlattice

AbstractNonlinear optical materials hold great promise for applications in advanced opto‐/opto‐electronic devices. However, achieving a substantial nonlinear absorption coefficient and modulation depth concurrently remains challenging. This study proposes an effective strategy for enhancing the nonlinear optical response of materials through the construction of hybrid inorganic–organic superlattices via convenient organic intercalation. Synthesizing SnS2 intercalated with various tetra‐alkylammonium cations, it is revealed that the optimized sample (SnS2/CTA: SnS2 intercalated with cetyltrimethylammonium, CTA+) exhibits a substantial enhancement of nonlinear absorption across a broad wavelength range (from 515 to 1550 nm) and for diverse nonlinear optical processes (saturable absorption, two‐photon absorption, and three‐photon absorption). Specifically, the SnS2/CTA demonstrates a third‐order nonlinear absorption coefficient of (9.847 ± 0.084) × 103 cm GW−1 and a 69% modulation depth under laser excitation at 800 nm. Under 1550 nm excitation, it displays a fifth‐order nonlinear absorption coefficient of (45.3 ± 1.2) cm3 GW−2 and a 62% modulation depth. Notably, these values surpass those of the majority of non‐exfoliated materials. Structural, spectral, and density functional theory calculations indicate no induced structure defects post‐organic intercalation. The observed bandgap reduction is attributed to the electron injection associated with the organic molecule intercalation. The calculated performance enhancement, based on dielectric enhancement and bandgap reduction, qualitatively aligns with experimental findings.

In Situ Synthesis of Polyaniline Nanohybrid and Formulation of Polyaniline/ Carboxymethyl cellulose/Ethylene Glycol Nanocomposite: Study of its Conducting and Antibacterial Properties

Polyaniline (PANI) has received great attention as a conducting polymer from researchers in the field of organic synthesis and development of conducting nanocomposite polymer technology for superconductors. Different methods of PANI synthesis are being sought for the obtainment of electrically robust PANI composites for electronic and other useful applications. Different inorganic matrices have been considered for this purpose. This study attempts to prepare PANI In situ on arginine-modified nanoclay template by chemical oxidation polymerization. Further, the PANI/Arginine-modified nanoclay was used to prepare PANI/Arginine-Nanoclay/Carboxymethyl cellulose/Ethylene glycol conducting film with robust electric conductivity (EC). Electrical conductivities, anti-bacterial evaluation, Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry analysis (TGA), differential thermogravimetry analysis (DTG) and Scanning Electron Microscopy (SEM) were used for the characterization studies and property evaluation. The electrical conductivities of PANI/Arginine-Nanoclay/Carboxymethyl cellulose/Ethylene glycol nanocomposite film reached 1900 S/Cm. FT-IR data, 3304–3196, 2926–2828, 2200–2022, 1733, 1620 and 1052 cm-1 respectively, confirmed the presence of organic intercalates, CMC, quinoid and benzenoid rings of PANI, and the inorganic nanoclay matter in the nanocomposite film. SEM revealed the presence of spine-like nanoflowers with elongated and expanded particle agglomerations. Thermal stability of the prepared nanocomposite thin film reached 700oC. The zone of inhibition ranged from 24-36 mm against S. typhi, E. coli and S. aureus. In conclusion, PANI nanocomposite thin conducting films had robust EC and antibacterial properties. In addition, the In-situ synthesis of PANI on Arginine-modified nanoclay platform aided the electric conductivity of the nanocomposite system.

Organic Intercalation Induced Kinetic Enhancement of Vanadium Oxide Cathodes for Ultrahigh-Loading Aqueous Zinc-Ion Batteries.

Vanadium-based oxides have attracted much attention because of their rich valences and adjustable structures. The high theoretical specific capacity contributed by the two-electron-transfer process (V5+ /V3+ ) makes it an ideal cathode material for aqueous zinc-ion batteries. However, slow diffusion kinetics and poor structural stability limit the application of vanadium-based oxides. Herein, a strategy for intercalating organic matter between vanadium-based oxide layers is proposed to attain high rate performance and long cycling life. The V3 O7 ·H2 O is synthesized in situ on the carbon cloth to form an open porous structure, which provides sufficient contact areas with electrolyte and facilitates zinc ion transport. On the molecular level, the added organic matter p-aminophenol (pAP) not only plays a supporting role in the V3 O7 ·H2 O layer, but also shows a regulatory effect on the V5+ /V4+ redox process due to the reducing functional group on pAP. The novel composite electrode with porous structure exhibits outstanding reversible specific capacity (386.7 mAh g-1 , 0.1 A g-1 ) at a high load of 6.5mg cm-2 , and superior capacity retention of 80% at 3 A g-1 for 2100 cycles.

Robustly Enhanced Seebeck Coefficient in the MXene/Organics/TiS2 Misfit Structure for Flexible Thermoelectrics.

The flexible thermoelectric (TE) generator has emerged as a superior alternative to traditional batteries for powering wearable electronic devices, as it can efficiently convert skin heat into electricity without any safety concerns. MXene, a highly researched two-dimensional material, is known for its exceptional flexibility, hydrophilicity, metallic conductivity, and processability, among other properties, making it a versatile material for a wide range of applications, including supercapacitors, electromagnetic shielding, and sensors. However, the low intrinsic Seebeck coefficient of MXene due to its metallic conducting nature poses a significant challenge to its TE application. Therefore, improving the Seebeck coefficient remains a primary concern. In this regard, a flexible MXene/organics/TiS2 misfit film was synthesized in this work through organic intercalation, exfoliation, and re-assembly techniques. The absolute value of Seebeck coefficient of the misfit film was significantly enhanced to 44.8 μV K-1, which is five times higher than that of the original MXene film. This enhancement is attributed primarily to the weighted effect of the Seebeck coefficient and possibly to energy-filtering effects at the heterogeneous interfaces. Additionally, the power factor of the misfit film was considerably improved to 77.2 μW m-1 K-2, which is 18 times higher than that of the original MXene film. The maximum output power of the TE device constructed of the misfit film was 95 nW at a temperature difference of 40 K, resulting in a power density of 1.18 W m-2, demonstrating the significant potential of this technology for driving low-energy consumption wearable electronics.

Organic-SnSe2 Hybrid Superlattice toward Synergistic Electrical Transport Optimization and Thermal Conductance Suppression.

Recently, layered SnSe2 has drawn broad research interest as a promising thermoelectric material that possesses great potential for application in energy conversion. However, extensive efforts have been devoted to optimizing the thermoelectric performance of SnSe2, but the ZT value is still far from satisfactory. Therefore, we developed an organic-inorganic superlattice hybrid by intercalating organic cations into SnSe2 interlayers in an attempt to enhance the thermoelectric properties. Organic intercalants can enlarge the basal spacing and decouple the SnSe2 layers, bringing about synergistic electrical transport modification and phonon softening. Thus, by simultaneously improving the electrical conductivity and reducing the thermal conductivity, a ZT value of 0.34 is achieved at 342 K in tetrabutylammonium-intercalated SnSe2, approximately two orders of magnitude higher than that of pristine SnSe2 single crystals. In addition, by opening van der Waals gaps via organic cations, outstanding flexibility of organic-intercalated SnSe2 is realized, with a superior figure of merit for flexibility of approximately 0.068. This work demonstrates a general and facile strategy to fabricate organic-inorganic superlattice hybrids with a considerable improvement in the thermoelectric performance via organic cation intercalation, which is promising for flexible thermoelectrics.

ZnF2-enabled preparation of Ti3C2Tx towards high-performance zinc-ion hybrid capacitors

MXenes have become a popular research topic, owing to their two-dimensional structure and superior properties. To promote practical applications of MXenes, there is an urgent need for a facile and cost-effective synthesis method. In this work, a low-cost alternative to conventionally used LiF, namely ZnF2, is employed to prepare Ti3C2Tx. And organic intercalants are not required during the delamination of as-produced multilamellar Ti3C2Tx. In addition, such ZnF2-involved etching method demonstrates similar yield and quality of Ti3C2Tx compared to the LiF/HCl etching method. The Ti3C2Tx prepared by ZnF2 etchant is combined with nanocellulose to form self-supporting composite films, which are explored as the cathodes for rechargeable zinc-ion hybrid capacitors (ZHCs). Thanks to the synergistic effect of Ti3C2Tx and nanocellulose, the optimized composite film exhibits high tensile strength of 59.7 MPa, large electrical conductivity of 24,754 S m−1, good electrolyte wettability, and superior electrochemical performances for ZHCs, such as large specific capacitance of 250.6F g−1 at 0.5 A g−1 and large capacity retention of 83.2% after 20,000 cycles. Moreover, the assembled quasi-solid-state ZHC displays satisfactory specific capacity and good endurance to deformations. This work unveils new insights into MXene synthesis and highlights their potential for high-performance energy storage devices.

Preparation and characterization of nanomuscovite by intercalation method for adsorption of heavy metals from polluted water

In this study, nanomuscovite adsorbents were prepared by intercalation with various organic intercalates (DTAB-TTAB-DTPA-PA-PN) and used to remove Cd2+ and Pb2+ from polluted water. The best nanomuscovite was prepared using DTPA and muscovite (Muc/DTPA) and characterized by XRD, TEM, EDX, FTIR, and BET surface area. The developed nanoadsorbent was used to remove Cd2+ and Pb2+ from polluted water. The effect of various factors, including contact time, adsorbent dosage, solution pH, and temperature, was investigated. The results reveal that the maximum adsorption of Cd2+ and Pb2+ was 91.5% and 97%, respectively, at the initial metal concentration 50 ppm, adsorbent dosage 0.2 g, contact time 60 min, solution temperature 25 °C, and pH 6 for Pb2+ and pH 7 for Cd2+. Adsorption isotherm models (Freundlich, Langmuir, Dubunin–Radushkevich, and Temkin isotherm models) as well as kinetic models (pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models) were employed to evaluate the experimental results. The adsorption of Cd2+ and Pb2+ on Muc/DTPA fitted well within the Langmuir isotherm model and followed pseudo-second-order kinetics. Thermodynamics parameters of metal adsorption indicated exothermic and spontaneous processes. Results were applied to the real wastewater that showed high Cd2+ and Pb2+ removal.

Rationally designed Dion-Jacobson Tin-halide perovskites with improved phase stability and Inter-layer charge transport by intercalating alkyl cation-ligands

Currently, the development of CsSnI3 perovskite is still greatly hindered by their intrinsic deficiencies, such as their easy phase transformation. To address this issue, we theoretically constructed Dion-Jacobson (DJ) perovskites intercalated by divalent 1,5-pentamethylenediamine (PeDA2+) exhibit significantly enhanced phase stability. However, the carrier mobility is always depressed owing to the charge localization and severe lattice distortion in the presence of spacers among wafers. Thus, the alkyl ligand cations (e.g., ethylenediamine (EDA), 1,3-propanediamine (PDA), 1,4-butanediamine (BDA)) with varying lengths as organic intercalators are examined for optimizing charge transfer. Compared with the other configures, the (PDA)Cs2Sn3I10 exhibits the most significantly improved stability due to the enhanced chemical bonding and faintest structural distortions, as evidenced by computed the formation enthalpy. Formation energy and transition level of tin-vacancy defect further confirm the improved stability and depressed defect-trapping states. Meanwhile, 2D-(PDA)Cs2Sn3I10 exhibit obviously increased electrical conductivity and reduced carrier effective masses, which might benefit the photoelectric conversion of solar cells.

Preparation of 2D Polyaniline/MoO3- x Superlattice Nanosheets via Intercalation-Induced Morphological Transformation for Efficient Chemodynamic Therapy.

Organic intercalation of layered nanomaterials is an attractive strategy to fabricate organic/inorganic superlattices for a wide range of promising applications. However, the synthesis of 2D organic/inorganic superlattice nanosheets remains a big challenge. Herein, the preparation of 2D polyaniline/MoO3- x (PANI/MoO3- x ) superlattice nanosheets via intercalation-induced morphological transformation from MoO3 nanobelts, as efficient Fenton-like reagents for chemodynamic therapy (CDT), is reported. Micrometer-long MoO3 nanobelts are co-intercalated with Na+ /H2 O followed by the guest exchange with aniline monomer for insitu polymerization to obtain PANI/MoO3- x nanosheets. Intriguingly, the PANI intercalation can induce the morphological transformation from long MoO3 nanobelts to 2D PANI/MoO3- x nanosheets along with the partial reduction of Mo6+ to Mo5+ , and generation of rich oxygen vacancies. More importantly, thanks to the PANI intercalation-induced activation, the PANI/MoO3- x nanosheets exhibit excellent Fenton-like catalytic activity for generation of hydroxyl radical (·OH) by decomposing H2 O2 compared with the MoO3 nanobelts. It is speculated that the good conductivity of PANI can facilitate electron transport during the Fenton-like reaction, thereby enhancing the efficiency of CDT. Thus, the polyvinylpyrrolidone-modified PANI/MoO3- x nanosheets can function as Fenton-like reagents for highly efficient CDT to kill cancer cells and eradicate tumors.

Effects of Typical Solvents on the Structural Integrity and Properties of Activated Kaolinite by Wet Ball Milling.

The influence of organic solvents on the structural integrity and properties of activated kaolinite were compared and analyzed via characterization techniques and molecular dynamics (MD) simulation. The results revealed that the organic intercalators can be easily inserted into the interlayer spaces of activated kaolinite within a short time of the wet ball milling. The DMSO intercalated kaolinites maintained structural integrity due to the high intercalation rate and the excellent buffering effect against the crushing force of milling during the delamination/exfoliation process. The delaminated layers of the DMSO-kaolinite complex exhibited a high specific surface area of 99.12 m2/g and a low average thickness of 35.21 nm. The calculated elastic properties of the organo-kaolinite complex manifested the intercalation of DMSO into a kaolinite interlayer, which could improve the compressibility and structural integrity of kaolinite nanosheets. The DMSO-kaolinite complex was easier to peel off when compared to the other organic intercalators due to its more intercalated molecules.

Interspace and Vacancy Modulation: Promoting the Zinc Storage of an Alcohol-Based Organic-Inorganic Cathode in a Water-Organic Electrolyte.

Expanding interspace and introducing vacancies are desired to promote the mobility of Zn ions and unlock the inactive sites of layered cathodes. However, this two-point modulation has not yet been achieved simultaneously in vanadium phosphate. Here, a strategy is proposed for fabricating an alcohol-based organic-inorganic hybrid material, VO1- x PO4 ·0.56C6 H14 O4 , to realize the conjoint modulation of the d-interspace and oxygen vacancies. Peculiar triglycol molecules with an inclined orientation in the interlayer also boost the improvement in the conversion rate of V5+ to V4+ and the intensity of the PO bond. Their synergism can ensure steerable adjustment for intercalation kinetics and electron transport, as well as realize high chemical reactivity and redox-center optimization, leading to at least 200% increase in capacity. Using a water-organic electrolyte, the designed Zn-ion batteries with an ultrahigh-rate profile deliver a long-term durability (fivefold greater than pristine material) and an excellent energy density of ≈142Whkg-1 (including masses of cathode and anode), thereby substantially outstripping most of the recently reported state-of-the-art zinc-ion batteries. This work proves the feasibility to realize the two-point modulation by using organic intercalants for exploiting high-performance new 2D materials.

Removing roadblocks and opening new opportunities for MXenes

The 2D carbides and nitrides, known as MXenes, are among the most recent, and quickly expanding, material families. The field is experiencing very fast growth with the number of papers on MXenes roughly doubling every year since their discovery in 2011. Great progress in synthesis and control of MXene properties has since been achieved. Synthesis of numerous theoretically predicted MXenes, including ordered solid solutions and high-entropy structures, led to the exploration of numerous applications. MXenes are not only promising candidates for energy storage and related electrochemical applications, such as electrocatalysis, but also applications in optoelectronics, plasmonics, electromagnetic interference shielding, medicine, sensing, catalysis and water desalination. We particularly focus on key material manufacturing and stability issues. We describe the scalable synthesis of MXenes by selective etching in aqueous acidic solutions; alternative synthesis methods, particularly fluorine-free synthesis; delamination without the use of organic intercalants; and improving the environmentally stability and shelf life of MXenes in colloidal suspensions. Finally, we discuss the current understanding of electronic transport in MXene films, which is of critical importance for many MXene applications.

3R-TaS2as an Intercalation-Dependent Electrified Interface for Hydrogen Reduction and Oxidation Reactions

Hydrogen technology, as a future breakthrough for the energy industry, has been defined as an environmentally friendly, renewable, and high-power energy carrier. The green production of hydrogen, which mainly relies on electrocatalysts, is limited by the high cost and/or the performance of the catalytic system. Recently, studies have been conducted in search of bifunctional electrocatalysts accelerating both the hydrogen evolution reaction (HER) and the hydrogen oxidation reaction (HOR). Herein, we report the investigation of the high efficiency bifunctional electrocatalyst TaS2 for both the HER and the HOR along with the asymmetric effect of inhibition by organic intercalation. The linear organic agent, to boost the electron donor property and to ease the process of intercalation, provides a higher interlayer gap in the tandem structure of utilized nanosheets. XRD and XPS data reveal an increase in the interlayer distance of 22%. The HER and the HOR were characterized in a Pt group metal-free electrochemical system. The pristine sample shows a low overpotential of −0.016 V at the onset. The intercalated sample demonstrates a large shift in its performance for the HER. It is revealed that the intercalation is a potential key strategy for tuning the performance of this family of catalysts. The inhibition of the HER by intercalation is considered as the increase in the operational window of a water-based electrolyte on a negative electrode, which is relevant to technologies of electrochemical energy storage.

Morphotype analysis and paleoecological implications of Maastrichtian - Paleogene benthic foraminifera from RCCG BH4 Borehole, Eastern Dahomey (Benin) Basin

The Maastrichtian-Eocene paleoecological conditions of eastern Dahomey (Benin) Basin were investigated using benthic foraminiferal morphotypes from the RCCG BH-4 borehole located on kilometer 46, Lagos-Ibadan Expressway, southwest Nigeria. Many previous studies on the basin and other Nigerian sedimentary basins centered on paleobathymetric studies using depth indicator benthic foraminiferal assemblages and planktic/benthic ratio. This present study attempts to categorize benthic species into morphological categories (morphotypes) based on general outline and shape, chamber arrangement, and mode of coiling, and use the distribution of the morphotypes to determine certain paleoecological conditions such as organic matter content, sediment pore water oxygen availability and sediment depositional setting. 25 ditch cutting samples subjected to the kerosene method of micropaleontological sample processing yielded few Maastrichtian – Eocene planktic species (Planoheterohelix globulosa, Morozovella acuta, Parasubbotina pseudobulloides, and Subbotina velascoensis) and fairly abundant and diverse benthic foraminiferal assemblages which we categorized into nine (9) morphotypes designated B2, B3, C1, F, H, I, J, N and Q. Six (6) of these morphotypes (B2, B3, I, J, N, and Q) are adapted to the epifaunal mode of life, while morphotypes C1, F, and H belong to the infaunal types. The dominance of the epifaunal morphotypes within the limestone Ewekoro Formation, and the underlying shaly sand unit of the Araromi Formation revealed a shallow marine (inner – middle neritic), low organic matter content, and oxygen-rich environment of deposition for these units. The infaunal morphotypes show sparse occurrence within the borehole except within the organic intercalation within the limestone unit in which 8 counts of Afrobolivina afra were recorded. The disappearance of species (faunal turnover) within the overlying shale unit (Akinbo Formation) is believed to be a response to heightened organic matter flux, reduced oxygen availability, and other climatic perturbations characteristic of the Paleocene-Eocene boundary. Eponides pseudoelevatus (morphotype N) is believed to be an opportunistic species based on the species’ continued occurrence and increased abundance within the shale unit (Akinbo Formation). The species may have recolonized the environment following improved environmental conditions that ensued after the cessation of the end Paleocene climatic perturbation.

N-p-Conductor Transition of Gas Sensing Behaviors in Mo2CTx MXene.

It is highly important to implement various semiconducting, such as n- or p-type, or conducting types of sensing behaviors to maximize the selectivity of gas sensors. To achieve this, researchers so far have utilized the n-p (or p-n) two-phase transition using doping techniques, where the addition of an extra transition phase provides the potential to greatly increase the sensing performance. Here, we report for the first time on an n-p-conductor three-phase transition of gas sensing behavior using Mo2CTx MXene, where the presence of organic intercalants and film thickness play a critical role. We found that 5-nm-thick Mo2CTx films with a tetramethylammonium hydroxide (TMAOH) intercalant displayed a p-type gas sensing response, while the films without the intercalant displayed a clear n-type response. Additionally, Mo2CTx films with thicknesses over 700 nm exhibited a conductor-type response, unlike the thinner films. It is expected that the three-phase transition was possible due to the unique and simultaneous presence of the intrinsic metallic conductivity and the high-density of surface functional groups of the MXene. We demonstrate that the gas response of Mo2CTx films containing tetramethylammonium (TMA) ions toward volatile organic compounds (VOCs), NH3, and NO2 is ∼30 times higher than that of deintercalated films, further showing the influence of intercalants on sensing performance. Also, DFT calculations show that the adsorption energy of NH3 and NO2 on Mo2CTx shifts from -0.973, -1.838 eV to -1.305, -2.750 eV, respectively, after TMA adsorption, demonstrating the influence of TMA in enhancing sensing performance.

Preparation of Dye Molecule-Intercalated MoO3 Organic/Inorganic Superlattice Nanoparticles for Fluorescence Imaging-Guided Catalytic Therapy.

Intercalation of organic molecules into the van der Waals gaps of layered materials allows for the preparation of organic/inorganic superlattices for varying promising applications. Herein, the preparation of a series of dye molecule/MoO3 organic/inorganic superlattice nanoparticles by aqueous intercalation of several dye molecules into layered MoO3 for fluorescence imaging-guided catalytic therapy is reported. The long MoO3 nanobelts are treated by ball milling and subsequent aqueous intercalation followed by a cation ion exchange to obtain the dye molecule-intercalated MoO3 organic/inorganic superlattices. Importantly, because of the activation induced by organic intercalation, the Nile blue (NB)-intercalated MoO3-x (NB-MoO3-x ) nanoparticles show excellent catalytic activity for the generation of reactive oxygen species, that is, hydroxyl radical (·OH) and superoxide anion (·O2- ), through catalyzing H2 O2 and O2 , respectively. Moreover, the intense fluorescence of the intercalated NB molecules endows NB-MoO3-x with the in vivo fluorescence imaging capability. Thus, the polyvinylpyrrolidone-modified NB-MoO3-x nanoparticles can be used for tumor-specific catalytic therapy to realize efficient cancer cell elimination in vitro and fluorescence imaging-guided tumor ablation in vivo.

Exploring Metastable Phases During Lithiation of Organic Battery Electrode Materials.

In this work, the Li‐ion insertion mechanism in organic electrode materials is investigated through the lens of atomic‐scale models based on first‐principles theory. Starting with a structural analysis, the interplay of density functional theory with evolutionary and potential‐mapping algorithms is used to resolve the crystal structure of the different (de)lithiated phases. These methods elucidate different lithiation reaction pathways and help to explore the formation of metastable phases and predict one‐ or multi‐electron reactions, which are still poorly understood for organic intercalation electrodes. The cathode material dilithium 2,5‐oxyterephthalate (operating at 2.6 V vs. Li/Li+) is investigated in depth as a case study, owing to its rich redox chemistry. When compared with recent experimental results, it is demonstrated that metastable phases with peculiar ring‐ring molecular interactions are more likely to be controlling the redox reactions thermodynamics and consequently the battery voltage.