In this review, the strategies to fabricate effective solid electrolyte interphase (SEI) for a stable Li-electrolyte interface are summarized. The designed inorganic artificial SEI, organic artificial SEI, and hybrid artificial SEI can significantly improve the electrochemical performance of Li metal anode. The strategies provide insights into Li metal protection.

Abstract

Li metal anode has attracted extensive attention as the state-of-the-art anode material for rechargeable batteries. It is defined as the ultimate anode material for the high theoretical specific capacity (3860 mAh g⁻¹) and the lowest negative electrochemical potential (−3.04 V vs. Standard Hydrogen Electrode). However, the uncontrolled Li dendrites and the spontaneous side reactions between Li and electrolytes hinder its commercialization. To overcome these obstacles, the optimized solid electrolyte interphase (SEI) with excellent performance was proposed by the artificial method. The improved performance includes high stability, ionic conductivity, compactness, and flexibility. In this review, the strategies for artificial SEI engineering in liquid and solid electrolytes are summarized. To fabricate an ideal artificial SEI, the component, distribution, and structure should be fully and reasonably considered. This review will also provide perspectives for the SEI design and lay a foundation for the future research and development of Li metal batteries.

A diastereoselective synthesis of pyrrolo/pyridoisoindole via alkyne iminium ion cyclization of vinylogous carbamate is described. This protocol features a broad substrate scope and easy scalability. An unusual 1,3-alkyl shift is observed with the substrates bearing a strong electron-donating group at the phenyl ring attached to alkyne.

Abstract

An efficient, acid-mediated, intramolecular alkyne iminium ion cyclization of oxoisoindolidene for the diastereoselective synthesis of pyrrolo/pyridoisoindole is described. This protocol features broad substrate scope and easy scalability. An unusual N to C-1,3-alkyl shift is observed with substrates bearing strong electron donating group at the phenyl ring attached to alkyne with concomitant hydration of alkyne to the ketone.

We report a novel alkynyl-protected Ag₂₀Rh₂ bimetallic nanocluster, which possesses unique structure and displays excellent catalytic performance toward hydrogen evolution reaction, 4-nitrophenol reduction, and methyl orange degradation.

Abstract

We report the overall structure and trifunctionality catalytic application of an atomically precise alloy nanocluster of Ag₂₀Rh₂(C≡C-^tBu)₁₆(CF₃CO₂)₆(H₂O)₂ (abbreviated as Ag₂₀Rh₂ hereafter). Ag₂₀Rh₂ has a twisted rod-like structure, where a Ag₄@Rh₂ kernel is connected by two twisted Ag₈ cubes on two sides. Ag₂₀Rh₂ is a superatomic cluster with four free valence electrons, and it has characteristic absorbance feature. Interestingly, Ag₂₀Rh₂ exhibited superior catalytic performance than the larger AgRh nanoparticle counterparts in electrochemical hydrogen evolution reaction (HER), reduction of 4-nitrophenol, and the methyl orange degradation reaction. Such intriguing catalytic properties are attributed to the more exposed active sites from the ultrasmall nanoclusters than relatively large nanoparticles. This study not only enriches the family member of alkynyl-protected AgRh nanoclusters with atomic precision, but also highlights the great advantages of employing nanoclusters as efficient catalysts for multiple functionalities.

The influence of surrounding temperature and electrical energetic condition on the conformational movements (cooperative actuation) of  polyindole is verified using a polyindole-coated polyvinyl alcohol (PIN/PVA) film.  Chronopotentiometric studies reveals that the consumed electrical energy during the reaction varies linearly with the change in working temperature. The influence of temperature on the reversible conformational movements of the polymer chain is related to the charge consumed during the reaction. The logarithmic dependence of  reversible redox charge obtained from coulovoltammogram  with inverse of temperature further proved the temperature sensing characteristics and the influence of temperature on the cooperative actuation of the PIN/PVA film. The conformational relaxation increases as the temperature increases through hosting higher number of counter anions with the solvent molecule.   The extension of the redox reaction or charge consumption  was found to decrease as the scan rate increases. The double logarithmic relation between the consumed redox charge and the scan rate has proved that the electrical energetic condition can influence the conformational movement or the extension of the redox reaction in a reversible manner. The results suggest that the PIN/PVA film can act as a biomimetic macro molecular sensor of working temperature and electrical energetic condition as biological muscles do.

Recent progress in the nanoscale synthesis of metal-containing nanoscale materials, ultra-high surface area nanoporous materials and other functionalities has exbited a notable significant impact on the field of hydrogen storage, particularly in the realm of storing molecular hydrogen, where these nanomaterials provide increased binding sites on the large surface and in the pores, more extensive surface area and porosity as well depth of physisorption at elevated temperatures may significantly boost H₂ storage capacity.

Abstract

The rapid advancement of refined nanostructures and nanotechnologies offers significant potential to boost research activities in hydrogen storage. Recent innovations in hydrogen storage have centered on nanostructured materials, highlighting their effectiveness in molecular hydrogen storage, chemical storage, and as nanoconfined hydride supports. Emphasizing the importance of exploring ultra-high-surface-area nanoporous materials and metals, we advocate for their mechanical stability, rigidity, and high hydride loading capacities to enhance hydrogen storage efficiency. Despite the evident benefits of nanostructured materials in hydrogen storage, we also address the existing challenges and future research directions in this domain. Recent progress in creating intricate nanostructures has had a notable positive impact on the field of hydrogen storage, particularly in the realm of storing molecular hydrogen, where these nanostructured materials are primarily utilized.

The dual operation of a chemical species in synthetic chemistry is an intriguing and relatively unexplored phenomenon. The application of such a species is expected to reduce the use of multiple reaction partners and catalysts/activators. Herein, we report a simple and easy-to-use protocol for the twin application of TiO(acac)2, as a reagent and an activator to synthesize β-enamino ketones with amines in acetonitrile. The same early transition metal precursor when employed in N,N-dimethylformamide with the amines, resulted in the formation of the substituted amides. Both reactions were explored with various substrates to check the viability of the present protocol. Moreover, experimental studies were conducted to understand the mechanism of both reactions.

Fluorination reactions are important in constructing organofluorine motifs in pharmaceuticals and agrochemicals, but they pose challenges due to their hazardous nature, high exothermicity, and limited selectivity and scalability. This review explores recent continuous flow techniques that addressed challenges of fluorination reactions, including gas-liquid reactions, packed-bed reactors, in-line purifications, reaction telescoping, large-scale reactions as well as flow photoredox- and electrocatalysis.

Abstract

Fluorination reactions are important in constructing organofluorine motifs, which contribute to favorable biological properties in pharmaceuticals and agrochemicals. However, fluorination reagents and reactions are associated with various problems, such as their hazardous nature, high exothermicity, and poor selectivity and scalability. Continuous flow has emerged as a transformative technology to provide many advantages relative to batch syntheses. This review article summarizes recent continuous flow techniques that address the limitations and challenges of fluorination reactions. Approaches based on different flow techniques are discussed, including gas-liquid reactions, packed-bed reactors, in-line purifications, streamlined multistep synthesis, large-scale reactions well as flow photoredox- and electrocatalysis.

Acacplatin-RB, a cisplatin analog having acetylacetone-appended to boron-dipyrromethene (BODIPY) dye, exhibits mitochondrial localization and remarkable apoptotic red-light induced photodynamic therapy (PDT) forming singlet oxygen as reactive oxygen species. Moreover, this complex demonstrated decrease in mitochondrial membrane potential, disruption of microtubules under photoinduced conditions and anti-metastatic properties from wound-healing assay.

Abstract

Cisplatin-derived platinum(II) complexes [Pt(NH₃)₂(pacac)](NO₃) (1, DPP-Pt) and [Pt(NH₃)₂(Acac-RB)](NO₃) (2, Acacplatin-RB), where Hpacac is 1,3-diphenyl-1,3-propanedione and HAcac-RB is a red-light active distyryl-BODIPY-appended acetylacetone ligand, are prepared, characterized and their photodynamic therapy (PDT) activity studied (RB abbreviated for red-light BODIPY). Complex 2 displayed an intense absorption band at λ=652 nm (ϵ=7.3×10⁴ M⁻¹ cm⁻¹) and 601 nm (ϵ=3.1×10⁴ M⁻¹ cm⁻¹) in 1 : 1 DMSO-DPBS (Dulbecco's Phosphate Buffered Saline). Its emission profile includes a broad maximum at ~673 nm (λ_ex=630 nm). The fluorescence quantum yield (Φ_F) of HAcac-RB and 2 are 0.19 and 0.07, respectively. Dichlorodihydrofluorescein diacetate and 1,3-diphenylisobenzofuran assay of complex 2 indicated photogeneration of singlet oxygen (Φ_Δ: 0.36) as reactive oxygen species (ROS). Light irradiation caused only minor extent of ligand release forming chemo-active cisplatin analogue. The complex showed ~70–100 fold enhancement in cytotoxicity on light exposure in A549 lung cancer cells and MDA-MB-231 multidrug resistant breast cancer cells, giving half maximal inhibitory concentration (IC₅₀) of 0.9–1.8 μM. Confocal imaging showed its mitochondrial localization and complex 2 exhibited anti-metastasis properties. Immunostaining of β-tubulin and Annexin V-FITC/propidium iodide staining displayed complex 2 induced photo-selective microtubule rupture and cellular apoptosis, respectively.

Zr-fum-MOF thin films of high optical quality were synthesized using the solvothermal direct growth method. The optical properties of the thin films were investigated thoroughly in different gas atmospheres.

Abstract

Crystalline Zr-fum-MOF (MOF-801) thin films of high quality are prepared on glass and silicon substrates by direct growth under solvothermal conditions. The synthesis is described in detail and the influence of different synthesis parameters such as temperature, precursor concentration, and the substrate type on the quality of the coatings is illustrated. Zr-fum-MOF thin films are characterized in terms of crystallinity, porosity, and homogeneity. Dense films of optical quality are obtained. The sorption behavior of the thin films is studied with various adsorptives. It can be easily monitored by measuring the transmission of the films in gas flows of different compositions. This simple transmission measurement at only one wavelength allows a very fast evaluation of the adsorption properties of thin films as compared to traditional sorption methods. The sorption behavior of the thin films is compared with the sorption properties of Zr-fum-MOF powder samples.

Conventional electrodes are now falling behind in meeting the increasing technological demands. Innovative and tailored electrodes are believed to be the most promising solution to the problem. Polymer composite electrodes are an optimistic class of tailored electrodes. This review outlines a bird-eye account of the carbon polymer composites and discusses the state-of-the-art on the Plastic Chip Electrode (PCE) comprehensively. PCE is a bulk conducting, self-standing, composite electrode fabricated by a spontaneous solvent-based method. The application of PCE as a multipurpose electrode platform is discussed here.

Abstract

The properties of electrodes play a crucial role in the processes occurring on them. Therefore, a variety of materials have been tried as electrodes. Carbon composite materials are among the most admired ones. Use of composites as electrode material dates back to the mid of the last century when polymer-carbon composites were tried as general-purpose electrode platforms and epoxy impregnated graphite paste/ solid electrodes were tried in polarography. Later the composite electrodes have seen several phases of development. Plastic Chip Electrode (PCE) is a class of polymer composite electrode developed by our group. This monographic review gives a bird‘s eye account of polymer composite electrodes and appurtenant work, followed by elaborating on various aspects and state-of-the-art plastic chip electrodes.