Magnesium hydride (MgH₂) is a promising solid-state hydrogen storage material due to its high hydrogen content and cyclic stability. However, its practical applications are limited by slow desorption kinetics and a high dehydrogenation temperature. To address these challenges, Pt-loaded MAX fibers with oxygen vacancies (Pt@MFs) have been synthesized by using vortex and hydrothermal methods. And the effects of the Pt@MFs on the hydrogen storage properties of MgH₂ are investigated. The results display that the MgH₂ doped with 10wt% Pt@MFs begins dehydrogenation at 169.3 ℃ and absorbs 5.73 wt% hydrogen in just 30 s at 125 ℃ and 30 bar hydrogen pressure. After 30 cycles, the MgH₂–10 wt% Pt@MFs retains 98.7% of its initial capacity, showcasing excellent cycling stability. The synergistic effect of the MAX fiber network’s active sites, oxygen vacancies, anchored Pt nanoparticles and intermetallic compounds (PtTi, Pt₃Ti) in the MgH₂–10 wt% Pt@MFs composite significantly enhances hydrogen storage kinetics by facilitating diffusion, optimizing electron transfer, and weakening Mg-H bonds. The design concept of this material offers a novel strategy for improving the kinetics and stability of MgH₂.

We devised a functional form stable composite phase-change materials (PCMs) to achieve a three-dimensional (3D) interconnected porous carbon aerogel structure for encapsulating polyethylene glycol (PEG). A novel homogeneity reinforced carbon aerogel with a well-interconnected porous structure was constructed by combining a flexible carbon resource from biomass guar gum with hard-brittle carbon from polyimide, to overcome severe shrinkage and poor mechanical performance of traditional carbon aerogel. The supporting carbon aerogel-encapsulated PEG produced the novel composite PCMs with good structure stability and comprehensive energy storage performance. The results showed that the composite PCMs displayed a well-defined 3D interconnected structure, and their energy storage capacities were 171.5 and 169.5 J/g, which changed only slightly after 100 thermal cycles, and the composites could maintain the equilibrium temperature at 50.0−58.1 °C for about 760.3 s. The thermal conductivity of the composites could reach 0.62 W m⁻¹ K⁻¹, which effectively enhanced the thermal response rate. And the composite PCMs exhibited good leakage-proof performance and excellent light–thermal conversion. The compressive strength of the composite PCMs can improve up to 1.602 MPa. Results indicate that this strategy can be efficiently used to develop novel composite PCMs with improved comprehensive thermal performance and high light–thermal conversion.