Sodium-ion batteries (SIBs) are regarded as promising alternatives to lithium-ion batteries (LIBs) in the field of energy, especially in large-scale energy storage systems. Tremendous effort has been put into the electrode research of SIBs, and hard carbon (HC) stands out among the anode materials due to its advantages in cost, resource, industrial processes, and safety. However, different from the application of graphite in LIBs, HC, as a disordered carbon material, leaves more to be completely comprehended about its sodium storage mechanism, and there is still plenty of room for improvement in its capacity, rate performance and cycling performance. This paper reviews the research reports on HC materials in recent years, especially the research process of the sodium storage mechanism and the modification and optimization of HC materials. Finally, the review summarizes the sterling achievements and the challenges on the basis of recent progress, as well as the prospects on the development of HC anode materials in SIBs.

Strict control of the monodispersity and size of nanoparticles less than 200 nm is a prerequisite for many applications. However, template- and surfactant-free synthesis of monodisperse polymers and carbon nanospheres less than 200 nm is still challenging. In this paper, new polymer nanospheres were first synthesized by a sol–gel method via the polycondensation of phloroglucinol, p-phenylenediamine, and formaldehyde based on the benzoxazine chemistry in the absence of templates and/or surfactants. We proved the formation of a polybenzoxazine structure and found that p-phenylenediamine not only participates in the condensation but also catalyzes the polymerization of phloroglucinol and formaldehyde based on the characterization by FTIR, Raman, NMR, and XPS. The monodisperse polymer nanospheres are so uniform that they can form three-dimensional periodic structures by self-assembly. In addition, these polymer nanospheres can be pseudomorphically converted to the corresponding uniform nitrogen-doped carbon spheres by pyrolysis due to the excellent thermal stability (48.6 wt% at 1000 °C based on the measurement of TGA) of such polybenzoxazine-based polymers. The high nitrogen doping level of 9.77 wt% in the carbon matrix was achieved. The sizes of the polymer and carbon nanospheres can be adjusted, respectively, in the range of 105–186 and 79.2–137 nm by changing the concentration of monomers and the ratio of ethanol to water. To demonstrate their applicability, the electrodes for supercapacitors were prepared using nitrogen-doped carbon nanospheres without any activation and showed excellent performance.

This study was undertaken to report the swift, facile and convenient synthesis of novel hydrazones obtained by condensation reaction between 2‐Amino‐3‐formylchromone and hydrazine derivatives. Various characterization techniques such as MALDI Mass, FTIR, ¹HNMR and ¹³CNMR spectrum analysis was done to determine the chemical structure of these novel six hydrazones. Furthermore, UV‐Vis and fluorescence spectra was studied to calculate λ_max and ε_max. These hydrazones are quite useful for their facile synthesis and chemical structure. Such hydrazones require separate clinical research to find their applications in biomedical fields.

Spinel oxide Co ₃ O ₄ nanoboxes boosted luminol/H ₂ O ₂ chemiluminescence by a factor of 670 and Mn ²⁺ significantly quenched chemiluminescence, enabling highly sensitive Mn ²⁺ detection.

The interaction of carbon (C) and nitrogen (N) single, double, and triple bonds with an aliphatic and aromatic carbon skeleton is widely used for medications and polymer synthesis. Many scientists have employed these compounds as target structures to determine their diverse chemical synthesis and use in various fields. The synthesis of polyglucose-hydrazide metal nanocomposites is a novel area of chemistry research. Polyglucose metal nanocomposites are widely used for drug delivery to target cancer and other lethal diseases. The major interests of this research were to synthesize, characterize, and find out the antibacterial properties of hydroxyl groups present in polyglucose-hydrazide metal nanocomposites. These nanocomposites were synthesized by acidification, esterification, and hydrazination of glucose and mixing of metal nanoparticles with polyglucose, respectively. The characterization of proposed nanocomposites was done by using scanning electron microscopy (SEM) and, energy dispersive X-Ray (EDX) spectroscopy. The biological activities of polyglucose-hydrazides cobalt, silver, and iron nano-composites were tested against Xanthomonas campestris malvacearum (a bacterial strain) by agar disc diffusion method. Amongst all, polyglucose-hydrazides cobalt nanocomposite yielded the highest antibacterial activity. Silver and iron nanocomposites also showed good activity. These results indicate that the antibacterial activities of metal nanoparticles are remarkably enhanced by combining with polyglucose hydrazide. These polyglucose-hydrazide metal nanocomposites have great potential as biocompatible antibacterial agents.