This investigation addressed the challenge of lead-containing wastewater treatment. We successfully synthesized a novel bimetallic magnetic adsorbent, MOF@Fe₃O₄-PAA, for Pb(II) removal by incorporating Ti ions via hydrothermal/chemical modification. Combined SEM, XRD, BET, FTIR, and XPS characterization elucidated its structure-property relationships. Results demonstrated optimal adsorption at pH 5.0 with a maximum capacity of 295.8 mg/g. Kinetics followed the pseudo-second-order model (R²=0.999), indicating chemisorption dominance. Isotherm analysis favored the Temkin equation (R²=0.979), suggesting combined physicochemical interactions. Thermodynamics revealed spontaneous exothermic adsorption (ΔG < 0, ΔH < 0) with enhanced efficacy at low temperatures. Selectivity tests showed significantly higher affinity for Pb(II) over competing ions (e.g., Cu²⁺, Zn²⁺). Amino (-NH₂) and sulfhydryl (-SH) functional groups enabled Pb(II) binding via coordination, yielding high adsorption capacity, rapid equilibrium attainment, and facile magnetic recovery. This work provides an innovative strategy for efficient wastewater Pb(II) removal.

Hydrogen energy has been recognized as “Ultimate Power Source” in the 21st century, which could be the best solution to the looming energy crisis and climate degeneration in the near future. Due to its high safety, low price, abundant resources and decent hydrogen storage density, magnesium based solid-state hydrogen storage materials are becoming the leading candidate for onboard hydrogen storage. However, the high operation temperature and slow reaction rate of MgH₂, as a result of the large formation enthalpy and high reaction activation energy, respectively, are the first and most difficult problems we need to face and overcome to realize its industrialization. Herein, a state-of-the-art review on tailoring the stable thermodynamics and sluggish kinetics of hydrogen storage in MgH₂, particularly through nanoengnieering and catalysis is presented, aiming to provide references and solutions for its promotion and application. Promising methods to overcome the challenges faced by MgH₂/Mg, such as bidirectional catalysts and nanoconfinement with in-situ catalysis are compared and the required improvements are discussed to stimulate further discussions and ideas in the rational design of MgH₂/Mg systems with ability for hydrogen release/uptake at lower temperatures and cycle stability in the near future.