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Although plenty of research studies have extensively focused on the synthesis of electrocatalysts with diverse methods, the synthesis of a high-performance electrocatalyst by a green and efficient method has still remained a vital problem that can seriously hamper the commercialization of fuel cell technology. Metallic aerogels recently appeared as a promising state-of-the-art class of self-supported architecture electrocatalyst materials because of their great electrocatalytic activity and enhanced stability for different electrochemical reactions. By taking advantage of the nanostructure engineering and new chemical reduction reaction, a novel, simple, eco-friendly, and surfactant-free procedure for the fabrication of self-assembled Pd aerogel is presented in this paper that uses the spontaneous one-step gelation process for synthesis. In contrast with other methods, our new method presents some advantages, such as being eco-friendly, simple, and having rapid synthesis. A palladium alcogel is prepared by reducing H2PdCl4 in ethanol utilizing C2H5OH/NaOH as a green reductant agent in a short time for the first time, and in the following step the palladium aerogel is obtained by supercritical drying. An extraordinary 3D nanonetwork of the Pd aerogel with large porosity is then affirmed using HRTEM, FESEM, XRD, EDX, and BET methods. Due to the profuse open interconnected pores and large inner surface areas, the Pd aerogel not only showed highly boosted electrocatalytic activity toward the ethanol oxidation reaction but also depicted much higher stability, durability, and mass activity in alkaline electrolyte than Pd/C. It is believed that the Pd aerogel prepared via a straightforward approach is an advanced candidate for applications in electrocatalysis for direct alcohol fuel cells and can create a great window of opportunity for different energy-related systems.

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Herein, a facile and low-cost route was used to prepare Polydopamine@Zeolitic Imidazolate Framework-67 (PDA@ZIF-67). The structure, morphology, surface functional groups and particle size distribution of PDA@ZIF-67 were studied using FTIR, FESEM, EDS, and BET analyses. The specific surface area and diameter of ​​PDA@ZIF-67 were equal to be 78.203 m2/g and 4.179 mm, respectively. The PDA@ZIF-67 was used as an adsorbent for the adsorption of methylene blue dye. The results show that the maximum adsorption efficiency of methylene blue on the surface of PDA@ZIF-67 is achieved at pH 2, the temperature of 65°C, 10 mg of adsorbent, and methylene blue concentration of 7.5 ppm.Moreover, the adsorption process's isothermal, thermodynamic, and kinetics were studied entirely to consider the adsorption mechanism. The methylene blue molecules located in the fine pores of the PDA@ZIF-67 adsorbent determine the adsorption rate. Moreover, the adsorption process of methylene blue at high temperatures is a spontaneous and endothermic reaction. The adsorption efficiency of PDA@ZIF-67, after the recovery, reached 62.21%, which is an excellent advantage for using this adsorbent.