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The growing demand for platinum group metals (PGMs) such as platinum (Pt) and palladium (Pd) necessitates novel approaches for efficient and selective separation and regeneration. Polyhedral oligomeric silsesquioxane (POSS)-based materials offer promising potential for retrieving PGMs from water, especially under raucous conditions. In this study, we present the first-ever development of a novel highly loaded carboxylic acid functionalized sulfur-containing POSS (POSS–S–COOH) through a one-step method. POSS–S–COOH demonstrated exceptional adsorption capabilities, with the highest adsorption capabilities for PtCl62− and PdCl42− measured at 597.2 ± 20.2 mg g−1 and 692.6 ± 25.1 mg g−1, respectively, in highly acidic water media. Remarkably, the adsorbent exhibited high selectivity toward PdCl42− and PtCl62− in the presence of various co-existing and common metal ions, such as Ni(II), Zn(II), Mg(II), Cu(II), Pb(II), Cd(II), Fe(III), and Co(II). Furthermore, it demonstrated proficient recovery capabilities for both PtCl62− and PdCl42− at pH 10, without the need for harsh desorbents such as thiourea, marking a significant achievement in this field. The pseudo-second-order as well as intraparticle diffusion kinetic and Langmuir isotherm data fitting indicated strong interactions resulting from electrostatic, H-bonding, and chelate bonding among the active functional sites of POSS–S–COOH and PtCl62−/PdCl42−. Thermodynamic analyses revealed spontaneous and endothermic adsorption of PtCl62− and PdCl42− by POSS–S–COOH. Density functional theory (DFT) calculations supported these findings, demonstrating high binding energy and low energy gaps, contributing to the proficient adsorption of PtCl62−/PdCl42− by POSS–S–COOH. Furthermore, POSS–S–COOH displayed excellent acid-resistance at pH 1, making it a promising adsorbent for potential industrial applications. This novel approach opens up new avenues for highly selective and easily regenerable POSS–S–COOH for the retrieval of precious metals from highly acidic water media. [ABSTRACT FROM AUTHOR]

Single‐atomic catalysts based on ruthenium have a balanced efficiency for water splitting, but it is necessary to control their activity and durability. In this work, a binder‐free Fe2‐xRuxNb2O6 (FRNO) hybrid catalyst is rationally designed through a facile hydrogel‐crosslinking route. The as‐prepared FRNO catalyst exhibits high electrocatalytic activity and stability when operating under acidic (0.5 m H2SO4) and alkaline (1 m KOH) media. Operando X‐ray adsorption and density functional theory calculations show that FRNO/CC, with its high intrinsic conductivity, promotes the adsorption and dissociation of water on its surface by regulating the charge distribution via charge transfer to the coordinated surface oxygen. This facilitates the oxygen evolution reaction (OER) performance by stabilizing *OOH adsorption on Ru and Fe. The FRNO/carbon cloth (CC) hybrid catalyst also delivers excellent activity and stability for both hydrogen evolution reaction (HER) and OER in pH‐universal electrolytes with low overpotentials of 30 mV per 82 mV for HER and 200 mV per 260 mV for OER at a current density of 10 mA cm‐2 in acidic/basic medium. Ultimately, the FRNO/CC hybrid catalyst shows good water‐splitting performance, and it is expected to help contribute to the creation of various hybrid electrocatalysts. [ABSTRACT FROM AUTHOR]