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1.
Chem Sci ; 15(31): 12169-12188, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39118630

RESUMEN

The pursuit of ultra-rapid, cost-effective, and accurate DNA sequencing is a highly sought after aspect of personalized medicine development. With recent advancements, mainstream machine learning (ML) algorithms hold immense promise for high throughput DNA sequencing at the single nucleotide level. While ML has revolutionized multiple domains of nanoscience and nanotechnology, its implementation in DNA sequencing is still in its preliminary stages. ML-aided DNA sequencing is especially appealing, as ML has the potential to decipher complex patterns and extract knowledge from complex datasets. Herein, we present a holistic framework of ML-aided next-generation DNA sequencing with domain knowledge to set directions toward the development of artificially intelligent DNA sequencers. This perspective focuses on the current state-of-the-art ML-aided DNA sequencing, exploring the opportunities as well as the future challenges in this field. In addition, we provide our personal viewpoints on the critical issues that require attention in the context of ML-aided DNA sequencing.

2.
Chem Sci ; 15(34): 13741-13752, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39211504

RESUMEN

Copper nanoclusters exhibit unique structural features and their molecular assembly results in diverse photoluminescence properties. In this study, we present ligand-dependent multicolor luminescence observed in a Cu14 cluster, primarily protected by ortho-carborane-9,12-dithiol (o-CBDT), featuring an octahedral Cu6 inner kernel enveloped by eight isolated copper atoms. The outer layer of the metal kernel consists of six bidentate o-CBDT ligands, in which carborane backbones are connected through µ3-sulphide linkages. The initially prepared Cu14 cluster, solely protected by six o-CBDT ligands, did not crystallize in its native form. However, in the presence of N,N-dimethylformamide (DMF), the cluster crystallized along with six DMF molecules. Single-crystal X-ray diffraction (SCXRD) revealed that the DMF molecules were directly coordinated to six of the eight capping Cu atoms, while oxygen atoms were bound to the two remaining Cu apices in antipodal positions. Efficient tailoring of the cluster surface with DMF shifted its luminescence from yellow to bright red. Luminescence decay profiles showed fluorescence emission for these clusters, originating from the singlet states. Additionally, we synthesized microcrystalline fibers with a one-dimensional assembly of DMF-appended Cu14 clusters and bidentate DPPE linkers. These fibers exhibited bright greenish-yellow phosphorescence emission, originating from the triplet state, indicating the drastic surface tailoring effect of secondary ligands. Theoretical calculations provided insights into the electronic energy levels and associated electronic transitions for these clusters. This work demonstrated dynamic tuning of the emissive excited states of copper nanoclusters through the efficient engineering of ligands.

3.
ACS Appl Mater Interfaces ; 16(33): 43591-43601, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39110785

RESUMEN

Designing dual-ion batteries (DIBs) by using various electrolytes through experiments or computationally is highly time-consuming and needs high-cost sophisticated resources. Here, we have utilized the ultrafast screening capability of machine learning (ML) to search for suitable salt-electrolytes toward the design of DIBs, choosing voltage as the desirable descriptor. Considering 50 different salts and their suitable staging mechanisms, the XGBoost Regressor ML model has been found to perform with remarkable accuracy. This is further validated by density functional theory, cross-validation, and experimental findings. An interpretable ML technique has been employed for local and global feature analysis to interpret the ML predicted results, underscoring the importance of choosing input features. This ML assisted DIB design approach has the potential to explore unknown salt-electrolytes that have yet to be tested in DIBs. Finally, we introduce the predicted voltages for all of the salt-electrolyte combinations as well as their probable staging mechanism. We signify the absence of a general trend in the predicted voltages, as various combinations of cations and anions are found to deliver unique voltages. Our study can guide researchers toward tuning constituent salts as well as staging mechanisms for the design of efficient DIBs.

4.
ACS Appl Mater Interfaces ; 16(32): 42138-42152, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39083029

RESUMEN

The compatibility between solvent electrolytes and high-voltage electrode materials represents a significant impediment to the progress of rechargeable metal-ion batteries. Rapidly identifying suitable solvent electrolytes with optimized electrochemical windows (ECWs) within an extensive search space poses a formidable challenge. In this study, we introduce a combined supervised and unsupervised (clustering) machine learning (ML) approach to discern distinct clusters of solvent electrolytes exhibiting varying ECW ranges. Through supervised machine learning, we have accurately predicted optimal solvent electrolytes with desired ECWs from a vast pool of 4882 solvents. Our ML model boasts superior accuracy compared to previously reported data from density functional theory (DFT). Besides, the exploration of the vast solvent space through K-means clustering (unsupervised approach) yields 11 optimal clusters, each encompassing different solvents characterized by diverse ECW ranges and frequencies. The expedited reduction of solvent space achieved through clustering occurs within a very short time frame and with minimal resource expenditure. Consequently, this method is highly capable of streamlining the subsequent experimental investigations for battery applications, avoiding the need for a trial-and-error approach.

5.
ACS Appl Mater Interfaces ; 16(29): 37994-38005, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38985897

RESUMEN

The commercial viability of emerging lithium-sulfur batteries (LSBs) remains greatly hindered by short lifespans caused by electrically insulating sulfur, lithium polysulfides (Li2Sn; 1 ≤ n ≤ 8) shuttling, and sluggish sulfur reduction reactions (SRRs). This work proposes the utilization of a hybrid composed of sulfiphilic MoS2 and mayenite electride (C12A7:e-) as a cathode host to address these challenges. Specifically, abundant cement-based C12A7:e- is the most stable inorganic electride, possessing the ultimate electrical conductivity and low work function. Through density functional theory simulations, the key aspects of the MoS2/C12A7:e- hybrid including electronic properties, interfacial binding with Li2Sn, Li+ diffusion, and SRR have been unraveled. Our findings reveal the rational rules for MoS2 as an efficient cathode host by enhancing its mutual electrical conductivity and surface polarity via MoS2/C12A7:e-. The improved electrical conductivity of MoS2 is attributed to the electron donation from C12A7:e- to MoS2, yielding a semiconductor-to-metal transition. The resultant band positions of MoS2/C12A7:e- are well matched with those of conventional current-collecting materials (i.e., Cu and Ni), electrochemically enhancing the electronic transport. The accepted charge also intensifies MoS2 surface polarity for attracting polar Li2Sn by forming stronger bonds with Li2Sn via ionic Li-S bonds than electrolytes with Li2Sn, thereby preventing polysulfide shuttling. Importantly, MoS2/C12A7:e- not only promotes rapid reaction kinetics by reducing ionic diffusion barriers but also lowers the Gibbs free energies of the SRR for effective S8-to-Li2S conversion. Beyond the reported applications of C12A7:e-, this work highlights its functionality as an electrode material to boost the efficiency of LSBs.

6.
J Am Chem Soc ; 146(30): 20937-20944, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-38979882

RESUMEN

Amidst burgeoning interest, atomically precise copper nanoclusters (Cu NCs) have emerged as a remarkable class of nanomaterials distinguished by their unparalleled reactivity. Nonetheless, the synthesis of hydride-free Cu NCs and their role as stable catalysts remain infrequently explored. Here, we introduce a facile synthetic approach to fabricate a hydride-free [Cu7(SC5H9)7(PPh3)3] (Cu7) NC and delineate its photophysical properties intertwined with their structural configuration. Moreover, the utilization of its photophysical properties in a photoinduced C-C coupling reaction demonstrates remarkable specificity toward cross-coupling products with high yields. The combined experimental and theoretical investigation reveals a nonradical mechanistic pathway distinct from its counterparts, offering promising prospects for designing hydride-free Cu NC catalysts in the future and unveiling the selectivity of the hydride-free [Cu7(SC5H9)7(PPh3)3] NC in photoinduced Sonogashira C-C coupling through a polar reaction pathway.

7.
J Am Chem Soc ; 146(29): 20183-20192, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39002137

RESUMEN

Polymer-based organic cathode materials have shown immense promise for lithium storage, owing to their structural diversity and functional group tunability. However, designing appropriate high-performance cathode materials with a high-rate capability and long cycle life remains a significant challenge. It is quintessential to design polymer-based electrodes with lithiophilic linkages. Herein, we design a bifurcated dibenzamide (DBA) linkage having lithiophilic functionalities. 1H NMR has been used as an experimental tool to understand the lithiophilic nature of the DBAs. Considering the strong Li+ affinity of DBAs, a series of polybenzamides have been designed as lithium storage systems. The design of porous polybenzamides consists of amides as only redox-active functionalities, and the rest are inactive phenyl units. Porous polybenzamides, when tested as cathodes against a Li-metal anode, displayed high capacity and rate performance, demonstrating their redox activity. The most efficient polybenzamide (TAm-TA) delivered a specific capacity of 248 mA h g-1 at 1C. TAm-TA retained 63% of its specific capacity at a very high rate of 10C (157 mA h g-1). Notably, polybenzamides displayed a capacity enhancement during long cycling, tending to achieve their theoretical capacity. Long cycling stability tests over 3000 cycles at a rate of 1.3C and over 6000 cycles at elevated rates (5C to 40C) demonstrate the electrochemical robustness of dibenzamide linkages. Finally, two full-cell experiments using TAm-TA as both cathode and anode were conducted, which delivered high capacity, demonstrating that TAm-TA is a promising candidate for Li+-ion batteries (LIBs). Furthermore, the ex situ Fourier transform infrared (FT-IR), X-ray photoemission spectroscopy (XPS), and density functional theory (DFT) studies revealed the stepwise lithiation/delithiation mechanism for polybenzamides.

8.
Anal Chem ; 96(28): 11516-11524, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38874444

RESUMEN

RNA sequence information holds immense potential as a drug target for diagnosing various RNA-mediated diseases and viral/bacterial infections. Massively parallel complementary DNA (c-DNA) sequencing helps but results in a loss of valuable information about RNA modifications, which are often associated with cancer evolution. Herein, we report machine learning (ML)-assisted high throughput RNA sequencing with inherent RNA modification detection using a single-molecule, long-read, and label-free quantum tunneling approach. The ML tools achieve classification accuracy as high as 100% in decoding RNA and 98% for decoding both RNA and RNA modifications simultaneously. The relationships between input features and target values have been well examined through Shapley additive explanations. Furthermore, transmission and sensitivity readouts enable the recognition of RNA and its modifications with good selectivity and sensitivity. Our approach represents a starting point for ML-assisted direct RNA sequencing that can potentially decode RNA and its epigenetic modifications at the molecular level.


Asunto(s)
Epigénesis Genética , Aprendizaje Automático , ARN , Análisis de Secuencia de ARN , ARN/genética , ARN/análisis , ARN/química , Análisis de Secuencia de ARN/métodos , Teoría Cuántica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos
9.
J Phys Condens Matter ; 36(39)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38914097

RESUMEN

Discovering high thermal conductivity materials is essential for various practical applications, particularly in electronic cooling. The significance of two-dimensional (2D) materials lies in their unique properties that emerge due to their reduced dimensionality, making them highly promising for a wide range of applications. Hexagonal boron nitride (BN), both monolayer and bilayer forms, has garnered attention for its fascinating properties. In this work, we focus on bilayer boron phosphide (BP), which is isostructural to its BN analogue. The lattice thermal conductivity of both bilayer BN and BP have been calculated usingab-initiodensity functional theory, machine learning with the moment tensor potential method, and the temperature-dependent effective-potential method (TDEP). The TDEP approach gives more accurate results for both BN and BP materials. The lattice thermal conductivity of bilayer BP is lower than that of bilayer BN at room temperature, attributed to increased phonon anharmonicity. This study highlights the importance of understanding phonon scattering mechanisms in determining the thermal conductivity of 2D materials, contributing to the broader understanding and potential applications of these materials in future technologies.

10.
Chem Sci ; 15(25): 9823-9829, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38939161

RESUMEN

Transformation chemistry of atomically precise metal nanoclusters has emerged as a novel strategy for fundamental research on the structure-property correlations of nanomaterials. However, a thorough understanding of the transformation mechanism is indeed necessary to understand the structural growth patterns and corresponding property evolutions in nanoclusters. Herein, we present the ligand-exchange-induced transformation of the [Au23(SR)16]- (8e-) nanocluster to the [Au25(SR')18]- (8e-) nanocluster, through the Au23(SR)17 (6e-) intermediate species. Identification of this key intermediate through a partially reversible transformation helped in a detailed investigation into the transformation mechanism with atomic precision. Moreover, photophysical studies carried out on this Au23(SR)17 species, which only differs by a single ligand from that of the [Au23(SR)16]- nanocluster reveal the property evolutions at the slightest change in the nanocluster structure.

11.
ACS Appl Mater Interfaces ; 16(23): 29891-29901, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38818926

RESUMEN

DNA sequencing with the quantum tunneling technique heralds a paradigm shift in genetic analysis, promising rapid and accurate identification for diverging applications ranging from personalized medicine to security issues. However, the widespread distribution of molecular conductance, conduction orbital alignment for resonant transport, and decoding crisscrossing conductance signals of isomorphic nucleotides have been persistent experimental hurdles for swift and precise identification. Herein, we have reported a machine learning (ML)-driven quantum tunneling study with solid-state model nanogap to determine nucleotides at single-base resolution. The optimized ML basecaller has demonstrated a high predictive basecalling accuracy of all four nucleotides from seven distinct data pools, each containing complex transmission readouts of their different dynamic conformations. ML classification of quaternary, ternary, and binary nucleotide combinations is also performed with high precision, sensitivity, and F1 score. ML explainability unravels the evidence of how extracted normalized features within overlapped nucleotide signals contribute to classification improvement. Moreover, electronic fingerprints, conductance sensitivity, and current readout analysis of nucleotides have promised practical applicability with significant sensitivity and distinguishability. Through this ML approach, our study pushes the boundaries of quantum sequencing by highlighting the effectiveness of single nucleotide basecalling with promising implications for advancing genomics and molecular diagnostics.


Asunto(s)
ADN , Aprendizaje Automático , ADN/química , Análisis de Secuencia de ADN/métodos , Nucleótidos/química , Nanotecnología/métodos
12.
Small ; : e2401112, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716623

RESUMEN

DNA sequencing is transforming the field of medical diagnostics and personalized medicine development by providing a pool of genetic information. Recent advancements have propelled solid-state material-based sequencing into the forefront as a promising next-generation sequencing (NGS) technology, offering amplification-free, cost-effective, and high-throughput DNA analysis. Consequently, a comprehensive framework for diverse sequencing methodologies and a cross-sectional understanding with meticulous documentation of the latest advancements is of timely need. This review explores a broad spectrum of progress and accomplishments in the field of DNA sequencing, focusing mainly on electrical detection methods. The review delves deep into both the theoretical and experimental demonstrations of the ionic blockade and transverse tunneling current methods across a broad range of device architectures, nanopore, nanogap, nanochannel, and hybrid/heterostructures. Additionally, various aspects of each architecture are explored along with their strengths and weaknesses, scrutinizing their potential applications for ultrafast DNA sequencing. Finally, an overview of existing challenges and future directions is provided to expedite the emergence of high-precision and ultrafast DNA sequencing with ionic and transverse current approaches.

13.
Nanoscale ; 16(10): 5257-5266, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38363168

RESUMEN

Non-aqueous Li-air batteries have garnered significant interest in recent years. The key challenge lies in the development of efficient catalysts to overcome the sluggish kinetics associated with the oxygen reduction reaction (ORR) during discharge and the oxygen evolution reaction (OER) during charging at the cathode. In this work, we conducted a comprehensive study on B/N-doped and BN co-doped fullerenes using first-principles analysis. Our results show significant changes in the geometries, electronic properties, and catalytic behaviors of doped and co-doped fullerenes. The coexistence of boron and nitrogen boosts the formation energy, enhancing stability compared to pristine and single-doped structures. C179B exhibits minimal overpotentials (0.98 V), implying superior catalyst performance for ORR and OER in LABs and significantly better performance than Pt (111) (3.48 V) and standard graphene (3.51 V). The electron-deficient nature of the B atom makes it provide its vacant 2pz orbital for conjugation with the p-electrons of nearby carbon atoms. Consequently, boron serves as a highly active site due to the localization of positive charge, which improves the adsorption of intermediates through oxygen atoms. Moreover, the higher activity of B-doped systems than N-doped systems in lithium-rich environments is opposite to the observed trend in the reported PEM fuel cells. This work introduces doped and co-doped fullerenes as LAB catalysts, offering insights into their tunable ORR/OER activity via doping with various heteroatoms and fullerene size modulation.

14.
Nanoscale ; 16(4): 1758-1769, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38167690

RESUMEN

The design of efficient electrocatalysts for improving hydrogen evolution reaction (HER) performance using atomically precise metal nanoclusters (NCs) is an emerging area of research. Here, we have studied the HER electrocatalytic performance of monometallic Cu6 and Au6 nanoclusters and bimetallic Au4Cu2 nanoclusters. A bimetallic Au4Cu2/MoS2 composite exhibits excellent HER catalytic activity with an overpotential (η10) of 155 mV vs. reversible hydrogen electrode observed at 10 mA cm-2 current density. The improved HER performance in Au4Cu2 is due to the increased electrochemically active surface area (ECSA), and Au4Cu2 NCs exhibits better stability than Cu6 and Au6 systems and bare MoS2. This augmentation offers a greater number of active sites for the favorable adsorption of reaction intermediates. Furthermore, by employing X-ray photoelectron spectroscopy (XPS) and Raman analysis, the kinetics of HER in the Au4Cu2/MoS2 composite were elucidated, attributing the favorable performance to better electronic interactions occurring at the interface between Au4Cu2 NCs and the MoS2 substrate. Theoretical analysis reveals that the inherent catalytic enhancement in Au4Cu2/MoS2 is due to favorable H atom adsorption over it and the smallest ΔGH* value. The downshift in the d-band of the Au4Cu2/MoS2 composite influences the binding energy of intermediate catalytic species. This new catalyst sheds light on the structure-property relationship for improving electrocatalytic performance at the atomic level.

15.
Nanoscale ; 16(7): 3583-3590, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38268470

RESUMEN

Atomically precise copper nanoclusters (Cu NCs), an emerging class of nanomaterials, have garnered significant attention owing to their versatile core-shell architecture and their potential applications in catalytic reactions. In this study, we present a straightforward synthesis strategy for [Cu29(StBu)12(PPh3)4Cl6H10][BF4] (Cu29) NCs and explore their catalytic activity in the carbonylative C-N coupling reaction involving aromatic amines and N-heteroarenes with dialkyl azodicarboxylates. Through a combination of experimental investigations and density functional theory studies, we elucidate the radical mechanisms at play. The crucial step in the catalytic process is identified as the decomposition of diisopropyl azodicarboxylates on the surface of Cu29 NCs, leading to the generation of oxyacyl radicals and the liberation of nitrogen gas. Subsequently, an oxyacyl radical abstracts a hydrogen atom from aniline, initiating the formation of an aminyl radical. Finally, the aminyl radical reacts with another oxyacyl radical, culminating in the synthesis of the desired carbamate product. This detailed analysis provides insights into the intricate catalytic pathways of Cu29 NCs, shedding light on their potential for catalyzing carbonylative C-N coupling reactions.

16.
Adv Mater ; 36(18): e2310938, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38245860

RESUMEN

The development of metal-free bifunctional electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER) is significant but rarely demonstrated. Porous organic polymers (POPs) with well-defined electroactive functionalities show superior performance in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Precise control of the active sites' local environment requires careful modulation of linkers through the judicious selection of building units. Here, a systematic strategy is introduced for modulating functionality to design and synthesize a series of thianthrene-based bifunctional sp2 C═C bonded POPs with hollow spherical morphologies exhibiting superior electrocatalytic activity. This precise structural tuning allowed to gain insight into the effects of heteroatom incorporation, hydrophilicity, and variations in linker length on electrocatalytic activity. The most efficient bifunctional electrocatalyst THT-PyDAN achieves a current density of 10 mA cm─2 at an overpotential (η10) of ≈65 mV (in 0.5 m H2SO4) and ≈283 mV (in 1 m KOH) for HER and OER, respectively. THT-PyDAN exhibits superior activity to all previously reported metal-free bifunctional electrocatalysts in the literature. Furthermore, these investigations demonstrate that THT-PyDAN maintains its performance even after 36 h of chronoamperometry and 1000 CV cycling. Post-catalytic characterization using FT-IR, XPS, and microscopic imaging techniques underscores the long-term durability of THT-PyDAN.

17.
Chemistry ; 30(6): e202302679, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37966848

RESUMEN

Establishment of a scaling relation among the reaction intermediates is highly important but very much challenging on complex surfaces, such as surfaces of high entropy alloys (HEAs). Herein, we designed an interpretable machine learning (ML) approach to establish a scaling relation among CO2 reduction reaction (CO2 RR) intermediates adsorbed at the same adsorption site. Local Interpretable Model-Agnostic Explanations (LIME), Accumulated Local Effects (ALE), and Permutation Feature Importance (PFI) are used for the global and local interpretation of the utilized black box models. These methods were successfully applied through an iterative way and validated on CuCoNiZnMg and CuCoNiZnSnbased HEAs data. Finally, we successfully predicted adsorption energies of *H2 CO (MAE: 0.24 eV) and *H3 CO (MAE: 0.23 eV) by using the *HCO training data. Similarly, adsorption energy of *O (MAE: 0.32 eV) is also predicted from *H training data. We believe that our proposed method can shift the paradigm of state-of-the-art ML in catalysis towards better interpretability.

18.
Inorg Chem ; 63(1): 316-328, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38114426

RESUMEN

Single-molecule spintronics, where electron transport occurs via a paramagnetic molecule, has gained wide attention due to its potential applications in the area of memory devices to switches. While numerous organic and some inorganic complexes have been employed over the years, there are only a few attempts to employ exchange coupled dinuclear complexes at the interface, and the advantage of fabricating such a molecular spintronics device in the observation of switchable Kondo resonance was demonstrated recently in the dinuclear [Co2(L)(hfac)4] (1) complex (Wagner et al., Nat. Nanotechnol. 2013, 8, 575-579). In this work, employing an array of theoretical tools such as density functional theory (DFT), the ab initio CASSCF/NEVPT2 method, and DFT combined with nonequilibrium Green Function (NEGF) formalism, we studied in detail the role of magnetic coupling, ligand field, and magnetic anisotropy in the transport characteristics of complex 1. Particularly, our calculations not only reproduce the current-voltage (I-V) characteristics observed in experiments but also unequivocally establish that these arise from an exchange-coupled singlet state that arises due to antiferromagnetic coupling between two high-spin Co(II) centers. Further, the estimated spin Hamiltonian parameters such as J, g values, and D and E/D values are only marginally altered for the molecule at the interface. Further, the exchange-coupled state was found to have very similar transport responses, despite possessing significantly different geometries. Our transport calculations unveil a new feature of the negative differential resistance (NDR) effect on 1 at the bias voltage of 0.9 V, which agrees with the experimental I-V characteristics reported. The spin-filtering efficiency (SFE) computed for the spin-coupled states was found to be only marginal (∼25%); however, if the ligand field is fine-tuned to obtain a low-spin Co(II) center, a substantial SFE of 44% was noted. This spin-coupled state also yields a very strong NDR with a peak-to-valley ratio (PVR) of ∼56 - a record number that has not been witnessed so far in this class of compounds. Additionally, we have established further magnetostructural-transport correlations, providing valuable insights into how microscopic spin Hamiltonian parameters can be associated with SFE. Several design clues to improve the spin-transport characteristics, SFE and NDR in this class of molecule, are offered.

19.
ACS Appl Mater Interfaces ; 15(47): 54520-54529, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37973157

RESUMEN

Dual-ion batteries (DIBs) represent a promising energy storage technology, offering a cost-effective safe solution with impressive electrochemical performance. The large combinatorial configuration space of the electrode-electrolyte leads to design challenges. We present a machine learning (ML) approach for accurately predicting the voltage and volume changes of polycyclic aromatic hydrocarbon (PAH) cathodes upon intercalation with a variety of DIB salts following different mechanisms. Gradient Boosting and XGBoost Regression models trained on the data set demonstrate exceptional performance in voltage and volume change prediction, respectively. The models are further cross-validated and utilized to predict the properties for ∼700 combinations of PAH and DIB salt intercalations, a subset of which is further validated by density functional theory. Using average voltage and volume change for all combinations of PAHs and salts, preferable combinations for high/low voltage requirements along with long-term stability are obtained. Overall, the study shows the applicability of PAHs in DIBs exhibiting good electrochemical performance with low volume change compared to graphite indicative of its potential to overcome the cycling stability issues of DIBs. This research establishes a reliable and broadly applicable ML-based workflow for efficient screening and accelerated design of advanced PAH cathodes and salts, thus driving progress in the field of DIBs.

20.
Inorg Chem ; 62(49): 20288-20295, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37988555

RESUMEN

Atom-precise metal nanoclusters, which contain a few tens to hundreds of atoms, have drawn significant interest due to their interesting physicochemical properties. Structural analysis reveals a fundamental architecture characterized by a central core or kernel linked to a staple motif with metal-ligand bonding playing a pivotal role. Ligands not only protect the surface but also exert a significant influence in determining the overall assembly of the larger superstructures. The assemblies of nanoclusters are driven by weak interaction between the ligand molecules; it also depends on the ligand type and functional group present. Here, we report an achiral ligand and Ag(I)···Ag(I) interaction-driven spontaneous resolution of silver-thiolate structure, [Ag18(C6H11S)12(CF3COO)6(DMA)2], where silver atoms and cyclohexanethiolate are connected to form a one-dimensional chain with helicity. Notably, silver atoms adopt different types of coordination modes and geometries. The photoluminescence properties of the one-dimensional (1D) chain structure were investigated, and it was found to exhibit excitation-dependent emission properties attributed to hydrogen-bonding interactions. Experimental and theoretical investigations corroborate the presence of triplet-emitting ligand-to-metal charge-transfer transitions.

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