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Organic oxidation reactions (OORs) powered by renewable energy sources are gaining importance as a favorable alternative to oxygen evolution reaction, with the promise of reducing the cell potential and enhancing the overall viability of the water electrolysis. This comprehensive review delves into the electrochemical oxidation of diverse organic compounds, including alcohols, aldehydes, amines, and urea, as well as biomass‐derived renewable feedstocks such as hydroxymethylfurfural and glycerol. The key focus centers on the role of nickel (Ni)‐based catalysts for these OORs. The unique redox activity and chemical nature of Ni have been proven instrumental for the sustainable and cost‐effective oxidation of various organic molecules more efficiently and selectively. This review article discusses how strategic choices, such as the selection of foreign metals, intercalating species, vacancies, defects, and a secondary element (e.g. chalcogens and non‐metals), contribute to tuning the electrochemical performances of a Ni‐based (pre)catalyst for OORs. Moreover, this review provides insights into the active species in various reaction environments and further explores reaction mechanisms, to apparent phase changes of the catalyst with the most relevant examples. Finally, the review not only elucidates the limitations of the current approaches but also outlines potential avenues for future advancements in OOR. [ABSTRACT FROM AUTHOR]

The urgent need for efficient oxygen evolution reaction (OER) catalysts has led to the development and publication of many heterostructured catalysts. The application of such catalysts with multiple phases tremendously increases the material design dimensions, and numerous interface‐related effects can tune the OER performance. In this regard, multiple of these heterostructured electrodes show remarkable OER activities. However, it is not clear if these carefully designed interfaces remain under prolonged OER conditions. Herein, a molecular approach is used to synthesize four different nickel‐iron phosphide (heterostructured) materials and deposit them on fluorine‐doped tin oxide and nickel foam electrodes. The OER performance of the eight electrodes and the reconstruction of the four materials is investigated by in‐situ spectroscopy after one day of operation, enabled by a freeze‐quench approach. The most active electrode is also applied under industrial OER conditions and for the value‐added oxidation of alcohols to ketones. Before catalysis, this electrode comprises crystalline 4 nm nickel phosphide particles on an amorphous iron phosphide matrix. However, after 24 h, a homogenous nickel‐iron oxyhydroxide phase has formed. This work questions to which extent the design of heterostructures is a suitable strategy for non‐noble metal OER catalysis. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most common highly aggressive malignant brain tumor, with a very limited chance for survival post-diagnosis and post-treatment. Despite significant advancement in GBM genomics implicated in molecularly targeted chemotherapies, the prognosis remains poor and requires new drug discovery approaches. We used fluoropyrimidine 5-fluorouracil (5-FU), an antimetabolite anticancer drug conjugated or 'caged' within a lipophilic Ru(II)-diphosphine (dppe) core formulated as [RuII(dppe)2(5-FU)]PF6 (Ru-DPPE-5FU), where dppe = 1,2-bis(diphenylphosphino)ethane, and evaluated its in vitro cytotoxicity in depth with aggressive GBM cells (LN229). The hydrophilic nature of 5-FU limits its passage through the blood–brain barrier (BBB), which prevents its effective accumulation and efficacy for GBM tumors. Herein, we attempted to modulate the lipophilicity of 5-FU by inserting it within a well-designed lipophilic {Ru(dppe)2}-core with anticipated higher efficiency towards GBM. The physicochemical properties of [RuII(dppe)2(5-FU)]PF6 (Ru-DPPE-5FU) were studied using various spectroscopic and analytical techniques. The molecular structure was determined using X-ray crystallography, showing a distorted {RuP4NO} octahedral geometry with bidentate (N, O) binding of 5-FU and its aromatization in the Ru(II)-bound form. The 31P-NMR spectra of Ru-DPPE-5FU showed four closely spaced distinct 31P-signals, indicating four unique chemical environments around P, and the strong coupling constants between them make it a second-order spectrum. The RuII/RuIII redox potential in Ru-DPPE-5FU shifted by ∼0.91 V towards the anodic region as compared to its precursor complex cis-[Ru(dppe)2Cl2] (Ru-DPPE-Cl). DFT-based theoretical calculations have been performed to correlate the experimental electronic absorption spectra and redox behaviours of the complexes. The electrostatic potential (ESP) plots indicate the delocalization of the charge density on the O-/F-atom from the 5-FU ligand towards Ru(II) upon its complexation. The antioxidant properties of all the compounds were quantified by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The hyphenation of the 5-fluorouracil (5-FU) ligand to the lipophilic {Ru(dppe)2}-core endowed lipophilicity to Ru-DPPE-5FU with higher in vitro cytotoxicity (IC50 = 2.37 μM) against the LN229 GBM cells as compared to the hydrophilic 5-FU, suggesting efficient cellular uptake. Further biological assays indicated that the complex is highly potent in inhibiting significant proliferation and spheroid formation and restricting the migratory potentials of the GBM cells. Increased caspase 3/7 activity and the presence of apoptotic bodies at the center of 3-D GBM spheroids as revealed by AO/EB dual staining indicated a deeper penetration of the lipophilic complex. The Ru-DPPE-5FU complex displayed lower cytotoxicity in HaCaT normal cells (IC50 = 7.27 μM) in comparison to LN229 cancer cells with a selectivity index (S.I.) of ≥3. Overall, the synergism and caging of 5-FU within the hydrophobic {Ru(dppe)2}-core improves the pharmacokinetic profile of Ru-DPPE-5FU as a potent anticancer agent for glioblastoma. [ABSTRACT FROM AUTHOR]

Electrochemical production of large-scale chemicals and fuels is critical to reaching carbon neutrality. However, the required anodic oxidation reactions, namely the oxygen evolution reaction (OER) or the oxidation of organics into value-added products, suffer from large overpotentials. To address this challenge, researchers have been widely investigating non-water-soluble (pre)catalysts to operate in the aqueous electrolyte. On the contrary, in this work, we approach a rapid, easy, and green carbon cloth electrode preparation using merely water-soluble nitrate precursors and ethanol as chemicals and no heating steps. The drop-coated, water-soluble transition metal salts reconstruct rapidly into the respective oxyhydroxides under OER conditions, with the oxyanion acting as a beneficial sacrificial reagent. This approach is shown herein for nickel(–iron) catalysts and their successful application for the OER (220 mV overpotential at 10 mA cm−2, long-term stability of 40 h at 100 mA cm−2) and the oxidation of 5-hydroxymethylfurfural (HMF, quantitative faradaic efficiency). We compare both reactions with both electrodes closely and find that the iron-free sample is more active for the HMF oxidation in regimes where mass transport is not the main limiting factor. We anticipate that this simple electrode preparation approach can find wide application in electrocatalysis and beyond. [ABSTRACT FROM AUTHOR]

Iron‐based (pre)catalysts have attracted enormous attention for various electrooxidation reactions due to the low cost, high abundance, and multiple accessible redox states of iron. Herein, a well‐defined helical iron borophosphate (LiFeBPO) is developed as an electro(pre)catalyst for the oxygen evolution reaction (OER) and selective alcohol oxidation. When deposited on nickel foam (NF), LiFeBPO exhibits an exceptional OER performance at ambient conditions attaining a current density of 100 mA cm−2 at ≈276 mV overpotential in 1 m KOH. Notably, this anode sustains durable alkaline water electrolysis at 500 mA cm−2 for over 330 h under industrial conditions (6 m KOH and 85 °C). In –situ and ex situ investigations reveal a deep reconstruction of LiFeBPO during OER, which transforms into a 3D open porous skeleton assembled by ultrasmall, low‐crystalline α‐FeOOH nanoparticles (interfacing with NiOOH of NF). This structure contributes to exposing accessible surface active sites, as well as accelerating mass transport and bubble detachment. Moreover, this electrode also catalyzes the electrooxidation of alcohols (methanol, ethylene glycol, and glycerol) to formic acid (FA) with high selectivity and full conversion. This study provides promising solutions for designing suitable anodes for the simultaneous production of green hydrogen fuel and value–added FA from electrooxidation reactions. [ABSTRACT FROM AUTHOR]

Aim: Enterotoxigenic Escherichia coli (ETEC) is one of the most widely recognized diarrhoeal pathogens in developing countries. The advancement of ETEC vaccine development depends on the antigenic determinants of the ETEC isolates from a particular geographical region. So, the aim here was to comprehend the distribution of virulence determinants of the clinical ETEC strains of this region. Additionally, an attempt was made to find any correlation with the antimicrobial response pattern. Methods and results: Multiplex PCR was employed to identify virulence determinants followed by confirmatory singleplex PCR. For observation of antibiotic response, the Kirby‐Bauer method was used. Out of 379 strains, 46% of strains harboured both the enterotoxins ST and LT, whereas 15% were LT only. Among the major colonization factors (CFs), CS6 (41%) was the most prevalent followed by CFA/I (35%) and CFA/III was the lowest (3%). Among the minor CFs, CS21 (25%) was most prevalent, while CS15 showed the lowest (3%) presence. Among the non‐classical virulence factors, EatA (69%) was predominant. ETEC strains harbouring CS6 showed resistance towards the commonly used drug Ciprofloxacin (70%). Conclusion: CS6 and elt+est toxin genes co‐occurred covering 51% of the isolates. CS21 was found in most strains with est genes (43%). EatA was found to occur frequently when ST was present alone or with LT. CS6‐harbouring strains showed an independent correlation to antimicrobial resistance. Significance and Impact of the Study: This study would aid in identifying the commonly circulating ETEC isolates of Kolkata, India, and their prevalent virulence determinants. Knowledge of antibiotic resistance patterns would also help in the appropriate use of antibiotics. Furthermore, the study would aid in identifying the multivalent antigens suitable for region‐specific ETEC vaccines with maximum coverage. [ABSTRACT FROM AUTHOR]

A pyrene‐hydroxyquinoline tethered ingeniously designed and developed azine based Schiff base luminophoric system, 2‐((Z)‐((E)‐(pyren‐1‐ylmethylene)hydrazono)methyl)quinolin‐8‐ol (PHQ) has been explored as a selective 'TURN ON' chromofluorogenic sensor for hazardous Hg2+ ions in ethanol/H2O (9 : 1,v/v) medium with detection limit of 0.22 μM and binding constant of 1.09 x 103 M−1. The detail scrutiny of mechanism of interaction between PHQ and Hg2+ is rationalized through various techniques like 1H NMR titration, FT‐IR, mass spectral analysis, theoretical computations, Job's plot, dynamic light scattering (DLS), transmission electron microscopy (TEM), time resolved excited state decay dynamics and fluorescence reversibility studies, which concretely declare a synergistic effect of supramolecular aggregation induced enhanced emission and deactivation of photo‐induced electron transfer (PET) processes. On the other hand, a 'TURN OFF' luminescence feature of highly fluorescent PHQ hydrosol is utilized for the selective screening of powerful explosive picric acid (PA) in aqueous medium and mechanism is deciphered by means of steady state, time‐resolved emission as well as computational studies which altogether reflect a combined effect of PET and ground state complexation between probe and PA. The commendable detection limit of 55 nM and Stern‐Volmer quenching constant of 1.48 x 104 M−1 with high quenching efficiency of 84% increases the pertinency of the nano‐probe. [ABSTRACT FROM AUTHOR]

Precise control of the topology of metal nanocrystals and appropriate modulation of the metal–semiconductor heterostructure is an important way to understand the relationship between structure and material properties for plasmon‐induced solar‐to‐chemical energy conversion. Here, a bottom‐up wet chemical approach to synthesize Au/Ni2P heterostructures via Pt‐catalyzed quasi‐epitaxial overgrowth of Ni on Au nanorods (NR) is presented. The structural motif of the Ni2P is controlled using the aspect ratio of the Au NR and the effective micelle concentration of the C16TAB capping agent. Highly ordered Au/Pt/Ni2P nanostructures are employed as the photoelectrocatalytic anode system for water splitting. Electrochemical and ultrafast absorption spectroscopy characterization indicates that the structural motif of the Ni2P (controlled by the outer‐shell deposition of Ni) helps to manipulate hot electron transfer during surface plasmon decay. With optimized Ni2P thickness, Pt‐tipped Au NR with an aspect ratio of 5.2 exhibits a geometric current density of 10 mA cm−2 with an overpotential of 140 mV. The photoanode displays unprecedented long‐term stability with continuous chronoamperometric performance of 50 h at an input potential of 1.5 V with over 30 days. This work provides definitive guidance for designing plasmonic–catalytic nanomaterials for enhanced solar‐to‐chemical energy conversion. [ABSTRACT FROM AUTHOR]