Per- and polyfluoroalkyl substances (PFASs) are a broad group of synthetic chemicals characterized by strong carbon–fluorine bonds, making them highly persistent and widely distributed in the environment. Their chain length and functional head groups, such as sulfonate and carboxylate groups, determine key molecular properties like hydrophobicity, acidity, and sorption behavior. These properties significantly impact the effectiveness of PFAS removal from water systems. This review provides a structural classification of PFASs and explores removal strategies, with a particular emphasis on adsorption. It examines sustainable adsorbents, including both natural materials (e.g., cellulose, chitosan, lignin, and cyclodextrins) and engineered synthetic materials (e.g., covalent organic frameworks, metal–organic frameworks, and molecularly imprinted polymers). The discussion highlights important parameters such as chain length and functional chemistry, as these can greatly influence removal efficiency. Furthermore, the discussion addresses the adsorption mechanisms-such as electrostatic attraction, hydrophobic interaction, and fluorophilic interactions-to show how they contribute in different systems. By combining structural insights with adsorption performance data, this review aims to help design and select sustainable, high-performance adsorbents for efficiently reducing PFASs in contaminated water.

Magnetite (Fe₃O₄) have been thoroughly investigated as microwave absorbing material due to its excellent electromagnetic properties (permittivity and permeability) and favorable saturation magnetization. However, large density and impedance mismatch are some of the limiting factors that hinder its microwave absorption performance (MAP). Herein, Fe₃O₄ nanoparticles prepared by facile co-precipitation method have been coated with citric acid and embedded in a polyvinylidene fluoride (PVDF) matrix. The coated Fe₃O₄ nanoparticles were characterized by X-ray diffraction spectrometer (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). COMSOL Multiphysics based on the finite element method was used to simulate the rectangular waveguide at X-band and Ku-band frequency range in three-dimensional geometry. The citric acid coated Fe₃O₄/PVDF composite with 40 wt.% filler loading displayed good microwave absorption ability over the studied frequency range (8.2–18 GHz). A minimum reflection loss of −47.3 dB occurs at 17.9 GHz with 2.5 mm absorber thickness. The composite of citric acid coated Fe₃O₄ and PVDF was thus verified as a potential absorptive material with improved MAP. These enhanced absorption coefficients can be ascribed to favorable impedance match and moderate attenuation.

Probing charge and energy transport in molecular junctions (MJs) has not only enabled a fundamental understanding of quantum transport at the atomic and molecular scale, but it also holds significant promise for the development of molecular-scale electronic devices. Recent years have witnessed a rapidly growing interest in understanding light-matter interactions in illuminated MJs. These studies have profoundly deepened our knowledge of the structure–property relations of various molecular materials and paved critical pathways towards utilizing single molecules in future optoelectronics applications. In this article, we survey recent progress in investigating light-driven charge transport in MJs, including junctions composed of a single molecule and self-assembled monolayers (SAMs) of molecules, and new opportunities in optical sensing at the single-molecule level. We focus our attention on describing the experimental design, key phenomena, and the underlying mechanisms. Specifically, topics presented include light-assisted charge transport, photoswitch, and photoemission in MJs. Emerging Raman sensing in MJs is also discussed. Finally, outstanding challenges are explored, and future perspectives in the field are provided.