In this study, we have successfully synthesized two non-metallic-based silicon corrole complexes (F10C-Si, F10C-CN-Si) and used them as HER electrocatalysts for the first time. Electrochemical studies indicate the electrocatalytic HER may go via EE-CEEC (E: electron transfer step, C: chemical step) pathway. Notably, it can be seen that the introduction of electron-withdrawing cyano group on the meso-phenyl of the corrole macrocycle may enhance the catalytic activity of silicon corrole complexes. In DMF with TsOH as the proton source, F10C-CN-Si exhibits a turnover frequency (TOF) of 331.48 s-1 and a high catalytic efficiency (C.E) of 1.29. Furthermore, the catalytic prowess of the silicon corrole complexes extends to neutral aqueous solution, with F10C-CN-Si achieving a TOF of 52.72 h⁻¹ at an overpotential of 1188 mV. This study extends the application of non-metallic-based silicon corrole molecular catalysts in the electrocatalytic HER field.

The development of multifunctional materials is an exceptional research area, which is aimed at enhancing the versatility of materials according to their wide fields of application. Special interest was devoted here to the orthophosphate compound, in particular, the olivine NaMnPO4 material. This compound was successfully synthesized by a solid-state method and characterized using various techniques. Preliminary room-temperature structural analysis evidences the sample formation in the orthorhombic structure and its phase purity. The material’s morphology, analyzed by scanning electron microscopy (SEM), is identified by a spherical grain size distribution. The average grain size of the sample was estimated to be around 420 nm. Moreover, the optical investigation of UV-visible spectroscopy has revealed that the band gap for our sample is (Eg = 2.28 eV), which shows that our compound is a potential candidate for optoelectronic applications. The electrical behavior study's main results confirm the ferroelectric character of the sample and support the aim of deepening the knowledge of the material according to its thermally stimulated conduction processes through impedance spectroscopy. Electrical studies revealed the dominant transport processes across various temperature and frequency ranges, leading to the NSPT model. The frequency dependency relates to frequency-dispersive dielectric spectra, conduction mechanisms, and relaxation phenomena.

A binuclear Co(II) complex, [Co2(PhBIMP)(μ-O2CPh)(MeCN)]2+ (1) ((PhBIMP is the anion of 2,6 bis[(bis((N-1-methyl-4,5-diphenylimidazoylmethyl) amino)methyl]-4-methylphenol)) catalyzes the hydrolysis of thiolates to the corresponding alcohols/phenols at room temperature. Hydrolysis of 11 different thiolates has been investigated with a catalyst loading of 4 - 6.7 mol% and with the highest TON values reaching 22. Furthermore, the effects of electron donating and electron withdrawing groups on the bridging benzoate of 1 have been investigated. The intermediates, products, and fate of the catalyst have been identified by mass spectrometric, gas chromatographic and gravimetric methods, and based on that, a mechanism for the catalytic cycle has been proposed.

Innovative therapeutic strategies are more than ever needed to counter the rise of antibiotic-resistant bacterial pathogens worldwide. The use of light, and especially photodynamic therapy (PDT) appears as a promising alternative or complement to antibiotic treatments, fostered by the development of new photosensitizers. In this study, eight luminescent Ir(III) complexes were synthesized and evaluated for their photoactivation properties and capacity to generate radical species under blue (452 nm), green (525 nm), and red (631 nm) LED light, respectively. Their antibacterial properties were assessed on Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus with most of these complexes exhibiting potentially useful activities upon light irradiation, at concentrations below 10 mg/L. A complex of Ir(III) cyclometallated to thiophenyl-isoquinoline (tiq) and bearing 2,2’-bipyridine (bipy) as ancillary ligand was further investigated. This latter showed a concentration- and light intensity-dependent bactericidal activity on P. aeruginosa when irradiated under blue to red lights, proving that such complexes would be suitable candidates for PDT. Importantly, this lead complex remained active against antibiotic resistant clinical strains and was unaffected by active efflux systems. These data open interesting perspectives for the development of new treatments to tackle antibiotic resistant Gram-negative bacteria.

A series of gold(I) phoshpine complexes with diverse alkynyl ligands [Au(C≡CR)(PTA)] (R= C6H11OH, 1; C5H9OH, 2; C15H11OH, 3; C19H27O2, 4; C18H23O2, 5; C9H12N, 6; CH2OCH2C6H5, 7; C6H4OCH3, 8; PTA =1,3,5-Triaza-7-phosphaadamantane) have been synthesized and characterized using a range of spectroscopic techniques. Complex 1 and 3 show an infinite one-dimensional S-type and zigzag aurophilic chain, respectively, whereas complex 2 containing 1-ethynyl-1-cyclohexanol gives an approximate linear two-dimensional aurophilic chain, through intra/intermolecular Au(I)···Au(I) interactions as well as hydrogen bonding interactions between hydroxy groups of alkynyl ligands and PTA. Solid Complexes 1-8 display strongly room/low-temperature emissive of 477–613 nm with the emission lifetime of 0.40-14.0 µs. All the complexes display higher cytotoxicities against MCF-7, with the cytotoxicity decreasing in the following order 4 > 8 > 5 > 3 > 7 > 6 > 2 > 1. Complex 4 and 5 stand out for the highest selectivity towards MCF-7 (IC50 =0.63-0.78 µM) compared with normal human embryonic lung fibroblasts (helf) (IC50 = 14.85-18.13 µM), which makes those complexes attractive for breast cancer therapy.

An accurate characterization methodology is indispensable to design nanoparticle-based drug delivery system (DDS) adapted to specific diseases and therapies. However, characterization techniques employed to investigate drug release and nanoparticle degradation require separating the nanoparticles from their suspension media, which can lead to artefacts. Therefore, there is a clear need to implement novel versatile in-situ methods. Here, we report the use of in-situ NMR spectroscopy to monitor drug delivery processes from MOF nanocarriers, both in solution and in the solid state simultaneously. In-situ1H NMR investigation of nanoMIL-100(Al) suspension in phosphate medium enabled recording the trimesate ligand loss in the solid phase and the ligand release in the liquid phase as a function of time. Simultaneously, 27Al NMR enabled assessing the progressive replacement of carboxylate ligands by phosphates leading to the formation of new aluminum species. Using the same strategy, we also compared the degradation of nanoMIL-100(Al) loaded with two drug analogs, highlighting an effect of metal-ligand complexing strength. Furthermore, our in-situ technique is applicable to studying the reaction of paramagnetic nanoMIL-100(Fe) in the liquid phase. This work offers an alternative to ex-situ techniques for understanding the degradation mechanism of MOF nanocarriers and could be an asset for other nanoscale DDSs.

Two-dimensional (2D) metal–organic frameworks (MOFs) have been a worldwide research interest due to their potential application in supercapacitors. Herein, a cobalt-based layered MOF ([Co2(μ-SO4)(Hppza)2(H2O)3]n, namely, SEU-1; H2ppza = 3-(pyridin-4-yl)-1H-pyrazole-5-carboxylic acid) has been synthesized via a one-step solvothermal method. Single X-ray diffraction analysis shows that the SEU-1 exhibits a (3,3,4)-connected 2D structure with a Schläfli symbol of (62·8)(63)(64·8·10). Variable-temperature magnetic susceptibility data display that antiferromagnetic interactions between two CoII ions exist in SEU-1. The supercapacitive performance has been evaluated in the three-electrode system. Its maximum specific capacitance is 145.5 F g−1 at 1 A g−1, along with the specific capacitance retention of 92.7% at the current density of 5 A g−1 after 6000 cycles in 3 M KOH solution. These results demonstrate that SEU-1 is a good candidate for electrode material for electrochemical energy storage.

This study explores the synthesis and diverse properties of newly synthesised water-soluble cobalt (II) complexes (1-3). Analysis of the complexes through various methods, including Hirshfeld surface analysis, reveals distinctive intermolecular interactions, particularly robust H-bonding contributions to crystal packing. 2D fingerprint plots provide quantitative insights into supramolecular interactions, while TGA-DSC analysis elucidates multi-step decomposition processes, mainly involving organic moieties. FT-IR and SCXRD confirm the structures of the complexes. Magnetic susceptibility measurements show paramagnetic behaviour in all complexes. FMO calculations expose HOMO-LUMO gaps and charge transfer processes, with NBO analysis emphasizing the significance of chloride, nitrogen, and oxygen atoms in coordination. In addition, pkCSM profile was carried out. The biological properties of the complexes reveal potent antibacterial activity for 2 and 3 against Gram-positive and Gram-negative bacteria. Despite lower antibacterial efficacy compared to standard antibiotics, their water solubility suggests potential human pharmacological applications. In terms of anti-inflammatory activity, all three complexes exhibit concentration-dependent prevention of ovalbumin denaturation, with 2 being the most effective. Compound 3, despite having seven carboxyl groups, exhibits the weakest anti-inflammatory effect, potentially attributed to complex formation obscuring these groups. Furthermore, all complexes display antioxidant activities; 1 and 2 are greater than BHT in the ferric thiocyanate assay.

New metastable SmSi3-x (x = 0-0.05) is obtained by high-pressure high-temperature synthesis (9.5 GPa, 870-1270 K). Powder diffraction data refinements reveal that the crystal structure of SmSi3 is isotypic to that of YbSi3 (space group I4/mmm, a = 7.23634(5) Å, c = 11.0854(1) Å). In the crystal structure, two types of Si2 dumbbells agglomerate into layers, which embed the samarium atoms. At ambient pressure, SmSi3 decomposes exothermally upon heating into Si and SmSi2-x. Single-crystal structure refinements of a specimen SmSi3-x (x=0.05) reveal considerable electron density, which is not accounted for by the YbSi3 model. The additional maxima can be assigned to disorder which affects the samarium positions and induces silicon vacancies. Scanning transmission electron microscopy experiments evidence that the disorder can be attributed to extended defects.  Magnetic measurements on SmSi3-x reveal van Vleck paramagnetic behavior and antiferromagnetic ordering at low temperatures. Computations within the local spin density approximation (LSDA and LSDA+U) on the crystal structure of SmSi3 reproduce the anti­ferro­magnetic coupling as the favored long-range order. Quantum chemical analysis of the chemical bonding in SmSi3 reveals two-center two-electron bonds within the Si2 dumbbells plus a total of a little less than four electrons in lone pairs at each silicon atom.

The substituents in 2,6-bis(2-R-2H-tetrazol-5-yl)pyridyl neutral ligands R2btp (R = Me, tBu) revealed a prominent effect when reacting with iron(II) salts, in combination with the nature of the anion. According to metal:ligand molar ratio, reaction of R2btp with FeCl2 led to isolate [FeII(R2btp-k3N,N’,N”)2](FeIIICl4)2, R = Me (1a) and tBu (2a), where the octahedral iron(II) centres bring two tridentate ligands in mer coordination mode, but also [FeII(tBu2btp-k3N,N’,N”)(tBu2btp-kN)2(H2O-kO)](FeIIICl4)2 (2b), where one ligand is tridentate, while the other two coordinate the iron(II) through one tetrazolyl nitrogen atom, and the octahedral sphere is completed by one water molecule. In all cases, half of the iron ions are oxidised to iron(III) forming the paramagnetic tetrachloroferrato counterions. Reaction of tBu2btp with Fe(ClO4)2×6H2O led to the octahedral [FeII(tBu2btp-k3N,N’,N”)2](ClO4)2∙4DCM (4a∙4DCM), which shows solvent-dependent spin crossover behaviour: while 4a∙4DCM is blocked in the high spin state, its unsolvated form, 4a, undergoes spin transition to low spin in two subsequent steps at 206 K, with opening of a 23-K hysteresis (T1/2¯ = 194 K, T1/2­ = 217 K), and at 136 K (T1/2¯ = 135 K, T1/2­ = 137 K). The magnetic profile changes to an incomplete spin transition when the sample absorbs water molecules yielding 4a×1.5H2O.