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Significant electrochemical properties improvement of poly ortho aminophenol (POAP) as conductive polymer and simultaneously as active electrode of electrochemical supercapacitor through fabricated POAP composite film in the presence of biopolymer chitosan (CTS) with porous structure was obtained. Nanocomposite morphology and information about POAP‐CTS interaction in the synthesized thin films were examined via scanning electron microscope. The surface area that depends on the porosity morphology was examined by Brunauere‐Emmette‐Teller (BET) analysis. Accordingly, the BET surface area, mean pore diameters, and single point total pore volume were measured as 39.044 m2 g−1, 19.68 nm, and 0.192 cm3 g−1, respectively. Electrochemical measurements like galvanostatic charge‐discharge experiments, cyclic voltammetry, and electrochemical impedance spectroscopy were investigated to examine the performance of the electrosynthesized composite (POAP/CTS) film. And also, the specific charge obtained as 345 F/g for POAP/CTS. In this work, a new considerable efficient polymeric composite in electrochemical redox capacitors with considerable advantages including ease synthesis, high active surface area, and stability in an aqueous electrolyte was introduced. Analysis of the quantum theory of atoms‐in‐molecules results shows that the chitosan system can be categorized into n‐type‐like (electron density donor) and p‐type‐like (electron density acceptor) sections and thus the parallel (in xy/yx plan) and perpendicular (in xz/yz plan) intramolecular sections have different electronic behaviors/electro‐chemical characterizations in molecule.

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In recent years, noise pollution has become one of the most critical human environmental problems. It has adverse effects on people's health and their work efficiency. Therefore, porous materials have gained enormous attention because they offer excellent sound absorption properties, low density, high specific strength, etc. In this review article, sound absorption in materials with specifically related properties such as sound absorption coefficient, sound absorption mechanisms, and types of metallic and non-metallic sound-absorbing foams are studied and discussed. Moreover, various kinds of porous polymeric materials are summarized, and in this respect polyurethane (PU) composite foams are represented with more details. Polyurethanes have several advantages such as reasonable physical, mechanical and thermal properties, acceptable processability, and chemical resistance. Polyurethane foam is a polymeric material with a cellular structure which makes it an effective sound absorber. Furthermore, various methods of preparing polymer foams are also presented. Different nanoparticles, synthetic and natural fibers are added to PU foam to enhance its acoustic properties. These additives and their effects on the sound absorption properties of PU foams are listed. Besides, various polymeric foam formation methods are explained with their advantages and disadvantages. Finally, discussion covers "porosity" as one of the most important factors on sound absorption properties of materials.

Biomass materials are abundant, low-cost, non-hazardous, disposable, environmentally friendly, and renewable organic materials considered as an appropriate solution for environmental contamination. Algae are renewable living organisms that are abundant throughout...