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Transition metal dichalcogenides (TMDs) are fascinating and prodigious considerations in the electrochemical energy storage sector because of their two dimensional chemistry as well as heterogeneous characteristics. Herein, we synthesized interconnected WS2 nanosheets by a hydrothermal method followed by sulphuration at 850 °C in an argon atmosphere. The ultrathin WS2 nanosheet array is endowed with an excellent specific capacitance of 74 F g−1 at the current density of 3 A g−1 up 7000 cycles. Moreover, a symmetric supercapacitor was fabricated using WS2 nanosheets, which provided the admirable high specific capacity of 6.3 F g−1 at 0.05 A g−1 with the energy and power density of 5.6 × 102 mW h kg−1 and 3.6 × 10 5 mW kg−1, respectively. Density functional theory (DFT) simulations revealed the presence of populated energy states near the Fermi level resulting in a high quantum capacitance value, which supports the experimentally achieved high capacitance value. The attained results recommend interconnected WS2 nanosheets as a novel, robust, and low-cost electrode material for supercapacitor energy storage devices. [ABSTRACT FROM AUTHOR]

Emulating angstrom-scale dynamics of the highly selective biological ion channels is a challenging task. Recent work on angstrom-scale artificial channels has expanded our understanding of ion transport and uptake mechanisms under confinement. However, the role of chemical environment in such channels is still not well understood. Here, we report the anomalously enhanced transport and uptake of ions under confined MoS2-based channels that are ~five angstroms in size. The ion uptake preference in the MoS2-based channels can be changed by the selection of surface functional groups and ion uptake sequence due to the interplay between kinetic and thermodynamic factors that depend on whether the ions are mixed or not prior to uptake. Our work offers a holistic picture of ion transport in 2D confinement and highlights ion interplay in this regime. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have attracted attention for quantum information science due to their ability to host single-photon emitters (SPEs). Although the properties of atomically thin materials are highly sensitive to surface modification, chemical functionalization remains unexplored in the design and control of 2D material SPEs. Here, we report a chemomechanical approach to modify SPEs in monolayer WSe2 through the synergistic combination of localized mechanical strain and noncovalent surface functionalization with aryl diazonium chemistry. Following the deposition of an aryl oligomer adlayer, the spectrally complex defect-related emission of strained monolayer WSe2 is simplified into spectrally isolated SPEs with high single-photon purity. Density functional theory calculations reveal energetic alignment between WSe2 defect states and adsorbed aryl oligomer energy levels, thus providing insight into the observed chemomechanically modified quantum emission. By revealing conditions under which chemical functionalization tunes SPEs, this work broadens the parameter space for controlling quantum emission in 2D materials. Single-photon emitters (SPEs) in 2D semiconductors are usually affected by complex spectral profiles that limit their understanding and applications. Here, the authors combine a noncovalent surface functionalization method with localized mechanical strain to simplify the spectra and enhance the purity of SPEs in monolayer WSe2. [ABSTRACT FROM AUTHOR]

Four photo‐catalysts of the general formula [Ir(CO6/ppy)2(L)]Cl where CO6=coumarin 6 (Ir1–Ir3), ppy=2‐phenylpyridine (Ir4), L=4′‐(3,5‐di‐tert‐butylphenyl)‐2,2′ : 6′,2′′‐terpyridine (Ir1), 4′‐(3,5‐bis(trifluoromethyl)phenyl)‐2,2′ : 6′,2′′‐terpyridine (Ir2 and Ir4), and 4‐([2,2′ : 6′,2′′‐terpyridin]‐4′‐yl)‐N,N‐dimethylaniline (Ir3) were synthesized and characterized. These photostable photo‐catalysts (Ir1–Ir3) showed strong visible light absorption between 400–550 nm. Upon light irradiation (465 and 525 nm), Ir1–Ir3 generated singlet oxygen and induced rapidly photo‐catalytic oxidation of cellular coenzymes NAD(P)H. Ir1–Ir3 showed time‐dependent cellular uptake with excellent intracellular retention efficiency. Upon green light irradiation (525 nm), Ir2 provided a much higher photo‐index (PI=793) than the clinically used photosensitizer, 5‐aminolevulinicacid (5‐ALA, PI>30) against HeLa cancer cells. The observed necro‐apoptotic anticancer activity of Ir2 was due to the Ir2 triggered photo‐induced intracellular redox imbalance (by NAD(P)H oxidation and ROS generation) and change in the mitochondrial membrane potential. Remarkably, Ir2 showed in vivo photo‐induced catalytic anticancer activity in mouse models. [ABSTRACT FROM AUTHOR]

An understanding of the temperature-dependenceof solubility ofcarbon dioxide (CO2) in water is important for many industrialprocesses. Voluminous work has been done by both quantum chemicalmethods and molecular dynamics (MD) simulations on the interactionbetween CO2and water, but a quantitative evaluation ofsolubility remains elusive. In this work, we have approached the problemby considering quantum chemically calculated total energies and thermalenergies, and incorporating the effects of mixing, hydrogen bonding,and phonon modes. An overall equation relating the calculated freeenergy and entropy of mixing with the gas-solution equilibrium constanthas been derived. This equation has been iteratively solved to obtainthe solubility as functions of temperature and dielectric constant.The calculated solubility versus temperature plot excellently matchesthe observed plot. Solubility has been shown to increase with dielectricconstant, for example, by addition of electrolytes. We have also foundthat at the experimentally reported concentration of enzyme RuBP inbundle sheath cells of chloroplast in C4green plants,the concentration of CO2can effectively increase by asmuch as a factor of 7.1–38.5. This stands in agreement withthe observed effective rise in concentration by as much as 10 times. [ABSTRACT FROM AUTHOR]

Intramolecular magnetic exchangecoupling constants are determined for seven isolated metaphenylene-baseddinitroxide diradicals by unrestricted density functional methodology(UDFT) using a number of hybrid functionals such as B3LYP, B3LYP-D3,M06-2X, HSE, and LC-ωPBE. Geometry optimizations for both tripletand broken symmetry solutions are performed with the 6-311G(d,p) basisset for all the molecules. In all cases, B3LYP somewhat overestimatesthe coupling constant, and M06-2X produces a more realistic value.The range-separated HSE and LC-ωPBE functional yield large deviationsfrom experiment. The nature of spin coupling agrees with the spinalternation rule and the calculated spin densities, in conjunctionwith the McConnell rule. It can also be explained in terms of thenondisjoint Single Occupied Molecular Orbital effect. Furthermore,it correlates with the calculated NICS(1) isotropic and zz and hyperfinecoupling constants. We also put forward a method for the determinationof the intramolecular (J) and intermolecular (J′) coupling constants from quantum chemical calculationson a one-dimensional chain of weakly bound diradicals. Two expressionsare derived for the energies of different spin states in terms of Jand J′. Exemplary UDFT computationsare done on the N-mers (N= 2–6)of two diradicals for which the crystal coordinates are available.The intramolecular and intermolecular coupling constants are determinedfrom the calculated UDFT energies. These are indeed in general agreementwith the measured coupling constants. [ABSTRACT FROM AUTHOR]

Wehave investigated the ground state spin of 10 pairs of possiblephotochromic diradical isomers by quantum chemical methods. Dihydrogenpyrenes and dinitrile pyrenes have been chosen as spacers with radicalcenters attached at (1,7) and (1,8) locations. Oxoverdazyl has servedas a radical center, and both C and N linkages have been investigated.Triplet molecular geometries have been optimized at the UB3LYP/6-311G(d,p)level. Single-point calculations on triplet and broken symmetry stateshave been performed using the 6-311(d,p) basis set. Careful designshave led to the prediction of strongly coupled dihydropyrene (DHP)isomers, and the cyclophenadiene (CPD) isomers have always been foundas weakly coupled. The effect of the functional M06-2X has been investigated.Calculated TDDFT spectra have been sufficient to guarantee photochromismof the designed diradicals. It has been estimated that compounds ofdiradicals with large coupling constants in the DHP form would showa pronounced change in molar susceptibility on photoconversion. Thishas led us to identify two molecules that can serve as a photomagneticswitch at room temperature. [ABSTRACT FROM AUTHOR]

Chemical modification is a powerful strategy for tuning the electronic properties of 2D semiconductors. Here we report the electrophilic trifluoromethylation of 2D WSe 2 and MoS 2 under mild conditions using the reagent trifluoromethyl thianthrenium triflate (TTT). Chemical characterization and density functional theory calculations reveal that the trifluoromethyl groups bind covalently to surface chalcogen atoms as well as oxygen substitution sites. Trifluoromethylation induces p-type doping in the underlying 2D material, enabling the modulation of charge transport and optical emission properties in WSe 2 . This work introduces a versatile and efficient method for tailoring the optical and electronic properties of 2D transition metal dichalcogenides., (© 2024 Wiley-VCH GmbH.)

Transition metal dichalcogenides (TMDs) are fascinating and prodigious considerations in the electrochemical energy storage sector because of their two dimensional chemistry as well as heterogeneous characteristics. Herein, we synthesized interconnected WS 2 nanosheets by a hydrothermal method followed by sulphuration at 850 °C in an argon atmosphere. The ultrathin WS 2 nanosheet array is endowed with an excellent specific capacitance of 74 F g -1 at the current density of 3 A g -1 up 7000 cycles. Moreover, a symmetric supercapacitor was fabricated using WS 2 nanosheets, which provided the admirable high specific capacity of 6.3 F g -1 at 0.05 A g -1 with the energy and power density of 5.6 × 10 2 mW h kg -1 and 3.6 × 10 5 mW kg -1 , respectively. Density functional theory (DFT) simulations revealed the presence of populated energy states near the Fermi level resulting in a high quantum capacitance value, which supports the experimentally achieved high capacitance value. The attained results recommend interconnected WS 2 nanosheets as a novel, robust, and low-cost electrode material for supercapacitor energy storage devices.

The development of Pt IV prodrugs that are reduced into the therapeutically active Pt II species within the tumor microenvironment has received much research interest. In order to provide spatial and temporal control over the treatment, there is a high demand for the development of compounds that could be selectively activated upon irradiation. Despite recent progress, the majority of Pt IV complexes are excited with ultraviolet or blue light, limiting the use of such compounds to superficial application. To overcome this limitation, herein, the first example of Pt IV prodrug nanoparticles that could be reduced with deeply penetrating ultrasound radiation is reported, enabling the treatment of deep-seated or large tumors. The nanoparticles were found to selectively accumulate inside a mouse colon carcinoma tumor upon intravenous injection and were able to eradicate the tumor upon exposure to ultrasound radiation., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Quantifying the content of metal-based anticancer drugs within single cancer cells remains a challenge. Here, we used single-cell inductively coupled plasma mass spectrometry to study the uptake and retention of mononuclear (Ir1) and dinuclear (Ir2) Ir III photoredox catalysts. This method allowed rapid and precise quantification of the drug in individual cancer cells. Importantly, Ir2 showed a significant synergism but not an additive effect for NAD(P)H photocatalytic oxidation. The lysosome-targeting Ir2 showed low dark toxicity in vitro and in vivo. Ir2 exhibited high photocatalytic therapeutic efficiency at 525 nm with an excellent photo-index in vitro and in tumor-bearing mice model. Interestingly, the photocatalytic anticancer profile of the dinuclear Ir2 was much better than the mononuclear Ir1, indicating for the first time that dinuclear metal-based photocatalysts can be applied for photocatalytic anticancer treatment., (© 2022 Wiley-VCH GmbH.)

Four photo-catalysts of the general formula [Ir(CO6/ppy) 2 (L)]Cl where CO6=coumarin 6 (Ir1-Ir3), ppy=2-phenylpyridine (Ir4), L=4'-(3,5-di-tert-butylphenyl)-2,2' : 6',2''-terpyridine (Ir1), 4'-(3,5-bis(trifluoromethyl)phenyl)-2,2' : 6',2''-terpyridine (Ir2 and Ir4), and 4-([2,2' : 6',2''-terpyridin]-4'-yl)-N,N-dimethylaniline (Ir3) were synthesized and characterized. These photostable photo-catalysts (Ir1-Ir3) showed strong visible light absorption between 400-550 nm. Upon light irradiation (465 and 525 nm), Ir1-Ir3 generated singlet oxygen and induced rapidly photo-catalytic oxidation of cellular coenzymes NAD(P)H. Ir1-Ir3 showed time-dependent cellular uptake with excellent intracellular retention efficiency. Upon green light irradiation (525 nm), Ir2 provided a much higher photo-index (PI=793) than the clinically used photosensitizer, 5-aminolevulinicacid (5-ALA, PI>30) against HeLa cancer cells. The observed necro-apoptotic anticancer activity of Ir2 was due to the Ir2 triggered photo-induced intracellular redox imbalance (by NAD(P)H oxidation and ROS generation) and change in the mitochondrial membrane potential. Remarkably, Ir2 showed in vivo photo-induced catalytic anticancer activity in mouse models., (© 2021 Wiley-VCH GmbH.)

Photocatalytic anticancer profile of a Ir III photocatalyst (Ir3) with strong light absorption, high turnover frequency, and excellent biocompatibility is reported. Ir3 showed selective photo-cytotoxicity against cisplatin- and sorafenib-resistant cell lines while remaining dormant to normal cell lines in the dark. Ir3 exhibited excellent photo-catalytic oxidation of cellular co-enzyme, the reduced nicotinamide adenine dinucleotide phosphate (NADPH), and amino acids via a single electron transfer mechanism. The photo-induced intracellular redox imbalance and change in mitochondrial membrane potential resulted in necrosis and apoptosis of cancer cells. Importantly, Ir3 exhibited high biocompatibility and photo-catalytic anticancer efficiency as evident from in vivo zebrafish and mouse cancer models. To the best of our knowledge, Ir3 is the first Ir III based photocatalyst with such a high biocompatibility and photocatalytic anticancer therapeutic effect., (© 2021 Wiley-VCH GmbH.)