Intercalation of pyrazine in layered copper nitroprusside: Synthesis, crystal structure and XPS study

Using -NH and -OH rich organic cathodes to explore proton transport in aqueous zinc-ion batteries

An organic cathode material for zinc-ion batteries shows a reliable proton transport mechanism. It uses a pyrazine ring as the energy storage unit and H+ as the shuttle ion, enabling high functionality utilization with rapid redox kinetics.

Solar-driven water evaporation using a collaborative photothermal conversion material system based on carbonized waste polyphenylene sulfide and copper sulfide

Recently, water resources have become scarce due to the growing global population and human impact on the environment, coupled with the effects of climate change. For solving the problem of global freshwater shortage and increasing the value of discarded polyphenylene sulfide (PPS) filter bags, in this study, balsa wood was used as the base of a photothermal solar evaporator, chitosan solution was used as the binder, and the main photothermal conversion materials used were polyphenylene sulfide (CP) carbide and copper sulfide. In order to create synergistic photothermal conversion materials, freeze-drying and in situ precipitation were used to deposit the photothermal conversion materials on top of the balsa wood. The prepared CP/CuS-wood evaporator has excellent water evaporation performance and light conversion capability, with a water evaporation rate of 2.68 kg m-2 h-1 and a photothermal conversion efficiency of 93.2% under simulated one solar intensity irradiation. In addition, the evaporator can effectively remove organic dyes such as methylene blue and methyl orange. The evaporator's durability and seawater desalination capability have also been confirmed through seawater desalination experiments and outdoor tests. Studies have shown that solar interface photothermal evaporators are a viable solution for desalination and wastewater treatment. This eco-friendly, economically viable and stable photothermal evaporator mentioned in this paper has pioneering features and will be a new paradigm for desalination and wastewater treatment.

Facile synthesis of copper nitroprusside chitosan nanocomposite and its catalytic reduction of environmentally hazardous azodyes

One of the biggest issues affecting the entire world currently is water contamination caused by textile industries' incapacity to properly dispose their wastewater. The presence of toxic textile dyes in the aquatic environment has attracted significant research interest due to their high environmental stability and their negative effects on human health and ecosystems. Therefore, it is crucial to convert the hazardous dyes such as methyl orange (MO) azo dye into environmentally safe products. In this context, we describe the use of Copper Nitroprusside Chitosan (Cu/SNP/Cts) nanocomposite as a nanocatalyst for the chemical reduction of azodyes by sodium borohydride (NaBH4). The Cu/SNP/Cts was readily obtained by chemical coprecipitation in a stoichiometric manner. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FT-IR) spectroscopy were applied to investigate chemical, phase, composition, and molecular interactions. Additionally, Scanning electron microscope (SEM) was used to examine the nanomaterial's microstructure. UV-vis spectroscopy was utilized for studying the Cu Nitroprusside Chitosan's catalytic activity for the reduction of azodye. The Cu/SNP/Cts nanocomposite demonstrated outstanding performance with total reduction time 160 s and pseudo-first order constant of 0.0188 s-1. Additionally, the stability and reusability study demonstrated exceptional reusability up to 5 cycles with minimal activity loss. The developed Cu/SNP/Cts nanocomposite act as efficient nanocatalysts for the reduction of harmful Methyl orange azodye.

Copper nitroprusside: An innovative approach for targeted cancer therapy via ROS modulation

The clinical application of nanomaterials for chemodynamic therapy (CDT), which generate multiple reactive oxygen species (ROS), presents significant challenges. These challenges arise due to insufficient levels of endogenous hydrogen peroxide and catalytic ions necessary to initiate Fenton reactions. As a result, sophisticated additional delivery systems are required. In this study, a novel bimetallic copper (II) pentacyanonitrosylferrate (Cu(II)NP, Cu[Fe(CN) 5 NO]) material was developed to address these limitations. This material functions as a multiple ROS generator at tumoral sites by self-inducing hydrogen peroxide and producing peroxynitrite (ONOO-) species. The research findings demonstrate that this material exhibits low toxicity towards normal liver organoids, yet shows potent antitumoral effects on High Grade Serous Ovarian Cancer (HGSOC) organoid patients, regardless of platinum resistance. Significantly, this research introduces a promising therapeutic opportunity by proposing a single system capable of replacing the need for H2O2, additional catalysts, and NO-based delivery systems. This innovative system exhibits remarkable multiple therapeutic mechanisms, paving the way for potential advancements in clinical treatments.

Silver nitroprusside as an efficient chemodynamic therapeutic agent and a peroxynitrite nanogenerator for targeted cancer therapies

INTRODUCTION

Chemodynamic therapy (CDT) holds great promise in achieving cancer therapy through Fenton and Fenton-like reactions, which generate highly toxic reactive species. However, CDT is limited by the lower amount of catalyst ions that can decompose already existing intracellular H2O2 and produce reactive oxygen species (ROS) to attain a therapeutic outcome.

OBJECTIVES

To overcome these limitations, a tailored approach, which utilizes dual metals cations (Ag+, Fe2+) based silver pentacyanonitrosylferrate or silver nitroprusside (AgNP) were developed for Fenton like reactions that can specifically kill cancer cells by taking advantage of tumor acidic environment without used of any external stimuli.

METHODS

A simple solution mixing procedure was used to synthesize AgNP as CDT agent. AgNP were structurally and morphologically characterized, and it was observed that a minimal dose of AgNP is required to destroy cancer cells with limited effects on normal cells. Moreover, comprehensive in vitro studies were conducted to evaluate antitumoral mechanism.

RESULTS

AgNP have an effective ability to decompose endogenous H2O2 in cells. The decomposed endogenous H2O2 generates several different types of reactive species (•OH, O2•-) including peroxynitrite (ONOO-) species as apoptotic inducers that kill cancer cells, specifically. Cellular internalization data demonstrated that in short time, AgNP enters in lysosomes, avoid degradation and due to the acidic pH of lysosomes significantly generate high ROS levels. These data are further confirmed by the activation of different oxidative genes. Additionally, we demonstrated the biocompatibility of AgNP on mouse liver and ovarian organoids as an ex vivo model while AgNP showed the therapeutic efficacy on patient derived tumor organoids (PDTO).

CONCLUSION

This work demonstrates the therapeutic application of silver nitroprusside as a multiple ROS generator utilizing Fenton like reaction. Thereby, our study exhibits a potential application of CDT against HGSOC (High Grade Serous Ovarian Cancer), a deadly cancer through altering the redox homeostasis.

Role of polymer template in crystal structure and photoactivity of Cu-TiO2 heterojunction nanostructures towards environmental remediation

Exploring porous heterojunction nanomaterials as a photocatalyst for water depollution strategies towards environmental restoration is exceedingly difficult in the perspective of sustainable chemistry. Herein, we first report a porous Cu-TiO₂ (TC40) heterojunction by using microphase separation of a novel penta-block copolymer (PLGA-PEO-PPO-PEO-PLGA) as a template through an evaporation induced self-assembly (EISA) method having nanorod-like particle shape. Furthermore, three types of photocatalysts were made with or without template polymer to clarify the function of that template precursor on the surface and morphology, as well as which variables are the most critical for a photocatalyst. TC40 heterojunction nanomaterial displayed high BET surface area along with lower band gap value viz.2.98 eV compare the other and all of these features make it a robust photocatalyst for wastewater treatment. In order to improve water quality, we have carried out experiments on the photodegradation of methyl Orange (MO), highly toxic pollutants that cause health hazards and bioaccumulate in the environment. Our catalyst, TC40 exhibits the 100% photocatalytic efficiency towards MO dye degradation in 40 and 360 min at a rate constant of 0.104 ± 0.007 min^-1 and 0.440 ± 0.03 h^-1 under UV + Vis and visible light irradiation respectively.

Iron nitroprusside as a chemodynamic agent and inducer of ferroptosis for ovarian cancer therapy

ChemoDynamic Therapy (CDT) is a powerful therapeutic modality using Fenton/Fenton-like reactions to produce oxidative stress for cancer treatment. However, the insufficient amount of catalyst ions and ROS scavenging activity of glutathione peroxidase (GPX4) limit the application of this approach. Therefore, a tailored strategy to regulate the Fenton reaction more efficiently (utilizing dual metal cations) and inhibit the GPX4 activity, is in great demand. Herein, a CDT system is based on dual (Fe²⁺ metals) iron pentacyanonitrosylferrate or iron nitroprusside (FeNP) having efficient ability to catalyze the reaction of endogenous H₂O₂ to form highly toxic ˙OH species in cells. Additionally, FeNP is involved in ferroptosis via GPX4 inhibition. In particular, FeNP was structurally characterized, and it is noted that a minimum dose of FeNP is required to kill cancer cells while a comparable dose shows negligible toxicity on normal cells. Detailed in vitro studies confirmed that FeNP participates in sustaining apoptosis, as determined using the annexin V marker. Cellular uptake results showed that in a short time period, FeNP enters lysosomes and, due to the acidic lysosomal pH, releases Fe²⁺ ions, which are involved in ROS generation (˙OH species). Western blot analyses confirmed the suppression of GPX4 activity over time. Importantly, FeNP has a therapeutic effect on ovarian cancer organoids derived from High-Grade Serous Ovarian Cancer (HGSOC). Furthermore, FeNP showed biocompatible nature towards normal mouse liver organoids and in vivo. This work presents the effective therapeutic application of FeNP as an efficient Fenton agent along with ferroptosis inducer activity to improve CDT, through disturbing redox homeostasis.

Nature of the observed ν(NO) band shift and splitting during the 3D to 2D structural change in transition metal nitroprussides

The electronic structure and related optical properties of the nitroprusside ion, [Fe(CN)₅NO]^2-, are dominated by the nitrosyl (NO⁺) group. The light-induced 2b₂(xy) → 7e(π*NO) (Fe → NO) and related appearance of meta-stable isomers for the NO group supports many of the functional properties of metal nitroprussides. In recent studies on the preparation of 2D transition metal nitroprussides from their 3D analogs, we have observed that such a structural change is concomitant with a decrease for the ν(NO) frequency and certain band splitting (unfolding). The 3D to 2D structural modification leads to an increase in the electron density at the iron atom. This results in an enhancement for the π*-back donation, which increases the electron population at the π*_2px and π*_2py orbitals. These last orbitals are doubly degenerated, and the increase for the π*-back bonding induces the removal of that degeneration via the Jahn-Teller effect. This intuitive mechanism explains the mentioned band unfolding related to the structural change. Such explanation was herein supported by a model based on the normal modes for the FeNO fragment derived from the small oscillation formalism around the equilibrium positions for the involved atoms. This model shows that there is a very close relationship between the deformation of the nitrosyl group (NO⁺) and the splitting of the IR bands. That is, the less linear the nitrosyl group, the greater the shift and splitting of the mentioned IR band. An excellent coincidence between the frequency values calculated using the model and the experimental ones was observed. The largest difference between the theoretically calculated ν(NO) frequencies and the experimental ones was only 6 cm^-1 and 5 cm^-1 in representative samples of 2D and 3D transition metal nitroprussides, respectively. The understanding of such an effect could be relevant for the functional properties of these 2D coordination polymers.

Controlled synthesis of trimetallic nitrogen-incorporated CoNiFe layered double hydroxide electrocatalysts for boosting the oxygen evolution reaction

The development of non-precious trimetallic electrocatalysts exhibiting high activity and stability is a promising strategy for fabricating efficient electrocatalysts for the oxygen evolution reaction (OER). In this study, trimetallic nitrogen-incorporated CoNiFe (N–CoNiFe) was produced to solve the low OER efficiency using a facile co-precipitation method in the presence of ethanolamine (EA) ligands. A series of CoNiFe catalysts at different EA concentrations were also investigated to determine the effects of the ligand in the co-precipitation of a trimetallic system. The introduction of an optimized EA concentration (20 mM) improved the electrocatalytic performance of N–CoNiFe dramatically, with an overpotential of 318 mV at 10 mA cm⁻² in 1.0 M KOH and a Tafel slope of 72.2 mV dec⁻¹. In addition, N–CoNiFe shows high durability in the OER process with little change in the overpotential (ca. 16.0 mV) at 10 mA cm⁻² after 2000 cycles, which was smaller than that for commercial Ir/C (38.0 mV).

A trimetallic nitrogen-incorporated CoNiFe exhibited good catalytic properties toward the oxygen evolution reaction, e.g., high stability and low overpotential (318 mV at 10 mA cm⁻²).

High performance based on quinoxalin-thiophene conjugated polymer composite carbon powder electrode material for Li-organic battery

In this work, thiophene derivatives were selected as donor units and pyrazine derivatives as receptor units to synthesize two composite materials consisting of supercapacitor carbon (SC) loaded with poly [2,3-bis (2-pyridinyl)-5,8-bis (2-thiophenyl) quinoxaline] (PPTQ) or poly [2,3-bis (2-pyridinyl)-5,8-bis (2-(3,4-ethylenedioxythiophene) quinoxaline] (PPETQ) by cationic radical polymerization. First, chemical bonds structure, surface morphology, and element valence states of these materials were characterized by infrared (IR), scanning electron microscopy (SEM) and XPS in turn. CV curves were used to determine their initial oxygen reduction potentials and to calculate their HOMO and LUMO values, both polymers have a narrow band gap, with Eg values lower than 2 eV. The polymer composite materials were tested as anodes in lithium-ion batteries, with a lithium sheet used as the counter electrode. Then the constant current charge-discharge and electrochemical impedance spectroscopy (EIS) impedance were measured. The first discharge specific capacities of PPTQ@SC and PPETQ@SC were 895.9 mAh/g and 913.0 mAh/g at a current density of 100 mA/g, the formation of a SEI film occurred in the second cycle, and their coulomb efficiencies can reach more than 90% from the third cycle, and the discharge platform appeared at about 1.0 V. In contrast, due to its stronger electron-donating ability, the PPETQ polymer containing the 3,4-ethylenedioxythiophene (EDOT) group have better electrical conductivity and its honeycomb structure provides more active sites for the lithiation/delithiation redox process. Therefore, the specific capacity of PPETQ@SC are all higher than that of PPTQ@SC at different current densities.

Low-Cost and Efficient Nickel Nitroprusside/Graphene Nanohybrid Electrocatalysts as Counter Electrodes for Dye-Sensitized Solar Cells

Novel nickel nitroprusside (NNP) nanoparticles with incorporated graphene nanoplatelets (NNP/GnP) were used for the first time as a low-cost and effective counter electrode (CE) for dye-sensitized solar cells (DSSCs). NNP was synthesized at a low-temperature (25 °C) solution process with suitable purity and crystallinity with a size range from 5 to 10 nm, as confirmed by different spectroscopic and microscopic analyses. The incorporation of an optimized amount of GnP (0.2 wt%) into the NNP significantly improved the electrocatalytic behavior for the redox reaction of iodide (I-)/tri-iodide (I3-) by decreasing the charge-transfer resistance at the CE/electrolyte interface, lower than the NNP- and GnP-CEs, and comparable to the Pt-CE. The NNP/GnP nanohybrid CE when applied in DSSC exhibited a PCE of 6.13% (under one sun illumination conditions) with the Jsc, Voc, and FF of 14.22 mA/cm2, 0.628 V, and 68.68%, respectively, while the PCE of the reference Pt-CE-based DSSC was 6.37% (Jsc = 14.47 mA/cm2, Voc = 0.635 V, and FF = 69.20%). The low cost of the NNP/GnP hybrid CE with comparable photovoltaic performance to Pt-CE can be potentially exploited as a suitable replacement of Pt-CE in DSSCs.

The adsorption performance and micro-mechanism of MoS2/montmorillonite composite to atenolol and acebutolol: Adsorption experiments and a novel visual study of interaction

MoS₂/montmorillonite (MoS₂/Mt) composite was successfully synthesized through a simple hydrothermal method, and its adsorption performance for two emerging contaminants-atenolol (ATE) and acebutolol (ACE) was researched. The batch experiments revealed that the adsorption process can be described by the Pseudo-second order model and Langmuir model, and the adsorption capacity of MoS₂/Mt, MoS₂ and Mt for ATE were 132.08 mg/g, 60.68 mg/g and 74.23 mg/g, for ACE were 113.82 mg/g, 33.01 mg/g and 36.05 mg/g, respectively. Besides, Fourier-transform infrared spectroscopy (FTIR), BET specific surface area measurement and X-ray photoelectron spectroscopy (XPS) were also employed to analyze the adsorption mechanism. Moreover, quantitative molecular surface analysis and weak intermolecular interaction analysis with independent gradient model were combined to probe the microscopic interaction between the adsorbent and adsorbate. The results indicated the interactions included hydrogen bonding and vdW interaction. Mt and MoS₂ interacted more strongly with ATE than ACE, which revealed the reason MoS₂/Mt, Mt and MoS₂ possessed higher adsorption capacity for ATE.

A first exploration of isostructurality in transition metal nitroprussides: X-ray analysis, magnetic properties and DFT calculations

Transition metal M(ii) (M = Mn, Fe, Cu, Zn, Cd) nitroprussides with 1-methyl-imidazole were prepared and characterized by spectroscopic techniques, thermal analysis, and powder (Fe complex) and single-crystal XRD.

CuICuII and AgIp-isocyanobenzoates as novel 1D semiconducting coordination oligomers

Two novel semiconducting coordination oligomers with 1D chain structures, namely [H0.07 CuI0.65CuII0.14(μ-p-CNC6H4CO2)·0.9H2O]n and [Ag(μ-p-CNC6H4CO2)]n, were obtained and characterized by XRD powder patterns, and XPS, EPR, UV-vis-NIR, IR and Raman spectroscopy. According to XRD analysis, CuICuII-ICNBA is an amorphous solid, while AgI-ICNBA crystalizes with a monoclinic unit cell in the C2/c space group (Z = 4). The composition and further information of CuICuII-ICNBA were obtained from the spectroscopic data. In correspondence with the quantification of terminal groups from high-resolution XPS spectra, CuICuII-ICNBA and AgI-ICNBA are composed of an average of 9 and 7 monomer units, respectively, resulting in 1D-oligomers. The spectroscopic evidence indicates that CuICuII-ICNBA is better described as a non-stoichiometric coordination oligomer (where non-integer ratios of metal ions can be accommodated), while AgI-ICNBA is stoichiometric. In both materials, each metal center is linked by two μ-η1:η1-p-isocyanobenzoate ligands forming microfibers of around 120 nm (CuICuII-material) and 310 nm (AgI-material) in average diameters with optical band gaps of 2.60 eV and 2.17 eV, respectively.

Detailing the Self-Discharge of a Cathode Based on a Prussian Blue Analogue

Prussian Blue analogues (PBAs) are a promising class of electrode active materials for batteries. Among them, copper nitroprusside, Cu[Fe(CN)5NO], has recently been investigated for its peculiar redox system, which also involves the nitrosyl ligand as a non-innocent ligand, in addition to the electroactivity of the metal sites, Cu and Fe. This paper studies the dynamics of the electrode, employing surface sensitive X-ray Photoelectron spectroscopy (XPS) and bulk sensitive X-ray absorption spectroscopy (XAS) techniques. XPS provided chemical information on the layers formed on electrode surfaces following the self-discharge process of the cathode material in the presence of the electrolyte. These layers consist mainly of electrolyte degradation products, such as LiF, LixPOyFz and LixPFy. Moreover, as evidenced by XAS and XPS, reduction at both metal sites takes place in the bulk and in the surface of the material, clearly evidencing that a self-discharge process is occurring. We observed faster processes and higher amounts of reduced species and decomposition products in the case of samples with a higher amount of coordination water.

Relevant electronic interactions related to the coordination chemistry of tetracyanometallates. An XPS study

In the K₂[M(CN)₄]·xH₂O (M = Ni, Pd, Pt) series, the CN ligand is found to donate electron density to the K ion, which is detected as a decrease in the K 2p BE. The charge donated is proportional to that removed from the inner metal (M) via π-back bonding.