In‐situ Generation of Hydroxyl Layers in CoO@FeSe2 Catalyst for High Selectivity Seawater Electrolysis

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Abstract

Seawater electrolysis holds great promise for hydrogen production in the future, while the development of anodic catalysts has been severely hampered by the side-reaction, chloride evolution reaction. In this work, nano-flower-cluster structured CoO@FeSe2/CF catalysts are synthesized via a scalable electrodeposition technique, and the performance is systematically studied. The oxygen evolution reaction (OER) overpotential of CoO@FeSe2/CF is 267 mV at 100 mA cm−2, which is significantly lower than the IrO2 catalyst (435 mV). Additionally, the catalyst shows high selectivity for OER (97.9%) and almost no loss of activity after a durability test for 1100 h. The impressive performance is attributed to the dense rod-like structure with abundant active centers after electrochemical activation and the in-situ generated CoOOH and FeOOH that improves the catalytic activity of the catalyst. The synergistic effect induced by the non-uniform structure endows the catalyst with excellent stability.

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Visible‐Light‐Initiated Air‐Oxygenation of Alkylarenes to Carbonyls Mediated by CBr4 in Water

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The proposal of synthesizing benzyl skeleton derivatives via direct oxidation of functionalized benzylic C–H bonds has received extensive research attention. Herein, a method was developed to prepare carbonyl compounds via photoinduced aerobic oxidation of ubiquitous benzylic C–H bonds mediated by bromine radicals and tribromomethane radicals. This method employed commercially available CBr4 as a hydrogen atom transfer reagent precursor, air as an oxidant, water as a reaction solvent, and tetra-butylammonium perchlorate (TBAPC) as an additive under mild conditions. A series of substrates bearing different functional groups was converted to aromatic carbonyls in moderate to good yields. Moreover, a low environmental factor (E-factor value = 0.45) showed that the proposed method is ecofriendly and environmentally sustainable.

Synthesis of new Fe(III), Co(II), and Cr(III) complexes of N‐(benzo[d]thiazol‐2‐ylcarbamothioyl)benzamide (H2L2): Structural characterization and biological activities

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Synthesis of new Fe(III), Co(II), and Cr(III) complexes of N-(benzo[d]thiazol-2-ylcarbamothioyl)benzamide (H2L2): Structural characterization and biological activities


N-(benzo[d]thiazol-2-ylcarbamothioyl)benzamide (H2L2) was synthesized as a novel thiosemicarbazide containing benzothiazole moiety, by the reaction of benzoyl isothiocyanate with 2-aminobenzothiazole in benzene. The (H2L2) thiosemicarbazide and its isolated Cr(III), Fe(III), and Co(II) complexes were fully analyzed by different spectroscopic techniques. The thermal fragmentation of [Cr (HL2)Cl2(H2O)2].10H2O, [Co (HL2)Cl(H2O)2].6H2O, and [Fe(L2)Cl(H2O)2] were analyzed. We have also calculated the thermal parameters with using two different methods. The ligand undergoes tranamidation in the presence of PdCl2. Crystal structure of the product obtained by tranamidation is measured. Biological activities of those compounds were assessed as antioxidants, anticancer, and antimicrobial.

Three heteroleptic copper(I) complexes with [Cu(P˄P)N2]+ structure and their fluorescence sensing for VOCs

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Three heteroleptic copper(I) complexes with [Cu(P˄P)N2]+ structure and their fluorescence sensing for VOCs


The design and research of luminescent and volatile organic compound (VOC) fluorescent sensing materials are of great significance and challenge. We report herein the ligand substitution reaction and VOC sensing of new heteroleptic [Cu(P˄P)N2]+ type copper(I) complexes. Firstly, three new complexes 1–3 were designed by utilizing a chelate diphosphine ligand 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos) and synthesized by the substitution reaction of different N-containing ligands of 4-PBO (1), 3-PBO (2), and 4,4′-Bipy (3) (4-PBO = 2-(4′-pyridyl)-benzoxazole, 3-PBO = 2-(3′-pyridyl)-benzoxazole, 4,4′-Bipy = 4,4′-bipyridine), respectively. Three complexes were characterized by elemental analysis, spectroscopic analysis (IR, UV–Vis), single-crystal X-ray diffraction (SCXRD), and photoluminescence study. The SCXRD study revealed that complexes 1 and 2 both exhibit a molecular structure with tetrahedral copper(I) complex cation and hexafluorophosphate anion, while complex 3 differs in that its cation is a binuclear copper(I) structure bridged by 4,4′-bipyridine. Three complexes 1–3 present supramolecular ribbon, supramolecular dimer, and supramolecular framework structure, respectively. Some differences of their UV–Vis absorption spectra were explained by TD-DFT calculation and wavefunction analysis. It is found that 1 has an abnormal luminescence blue shift, and a luminescence mechanism through the high-energy T2 excited state is proposed by TD-DFT calculation. Based on 3, a fluorescent test strip was developed, and its fast and selective fluorescent sensing of pyridine vapor through quenching mechanism was successfully realized. The fluorescent quenching mechanism of the material was also studied, and it was proposed that the quenching should be attributed to the photoinduced electron transfer (PET) mechanism.

Exploring phosphoryl oxygen basicity in U(VI) complexation: A comparative study from trialkyl phosphate to phosphine oxide

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Exploring phosphoryl oxygen basicity in U(VI) complexation: A comparative study from trialkyl phosphate to phosphine oxide

Basicity of Phosphoryl Group: The study examines the role of orbital overlap, dispersion interactions, charge transfer, and dipole moments of the resulting complexes, in understanding the increasing U(VI) extraction behavior across the ligand series phosphate → phosphonate → phosphinate → phosphine oxide.


Abstract

The conventional argument that extraction efficiency depends on the “basicity of the phosphoryl oxygen” is thoroughly examined in this study. The analysis involves studying the electronic structures of various ligands, such as phosphate, phosphonate, phosphinate, and phosphine oxide, as well as variations in their alkyl chain length, and their corresponding uranium complexes. The studies revealed a significant amount of destabilizing strain and steric repulsion for ligands having longer alkyl chains upon complexation. A considerable amount of stabilizing orbital and dispersion interactions compensate for these repulsions, forming stable complexes. Dispersion interactions become more significant upon chain elongation and are mainly responsible for the preference for U(VI) metal ions by ligands with lengthy alkyl chain units. The preference of phosphine oxide ligands for U(VI) is analyzed within the context of enhanced orbital interactions resulting from the energetically close donor (ligand) and acceptor (metal nitrate) orbitals. Additionally, dispersion-based interactions also become significant, especially with larger chain lengths. The electronegative environment around the phosphorus atom, along with the existence of low-dipole moment structures, is also examined in relation to their possible role in solvent extraction and their influence on the selectivity of ligands for uranyl species.

COVID‐19: Medical Waste Management, Impact on Sustainable Development Goals, and Bibliometric Analysis

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COVID-19: Medical Waste Management, Impact on Sustainable Development Goals, and Bibliometric Analysis

Sustainable and innovative solutions for managing medical waste and mitigating its impact on public health and environment are reviewed. Focusing on the sustainable development goals (SDGs), various methods of medical waste management are evaluated. The findings underscore the need for international collaboration and further research to achieve the SDGs and address medical waste management challenges.


Abstract

This comprehensive review examines various methods of treating medical waste in the context of the sustainable development goals (SDGs). A bibliometric analysis was conducted to investigate the impact of COVID-19 on medical waste, which showed a notable increase in publications in recent years. Findings indicate that thermal treatment with energy recovery, including pyrolysis, gasification, oxidation, and plasma gasification, is the most effective approach for managing medical waste. However, research on the impacts of medical waste on SDGs is insufficient, warranting further investigations to better understand the intersections between medical waste management and the SDGs. The need for international cooperation and collaboration in addressing medical waste management challenges, especially during crises, is highlighted. Understanding the links between medical waste management and the SDGs is crucial in developing sustainable solutions aligned with the global sustainability agenda. Further research and international collaboration are needed to address the challenges associated with medical waste management and contribute to the achievement of the SDGs.