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Hydrogen storage in MgH2 is an ideal solution for realizing the safe storage of hydrogen. High operating temperature, however, is required for hydrogen storage of MgH2 induced by high thermodynamic stability and kinetic barrier. Herein, flower‐like microspheres uniformly constructed by N‐doped TiO2 nanosheets coated with TiN nanoparticles are fabricated to integrate the light absorber and thermo‐chemical catalysts at a nanometer scale for driving hydrogen storage of MgH2 using solar energy. N‐doped TiO2 is in situ transformed into TiNxOy and Ti/TiH2 uniformly distributed inside of TiN matrix during cycling, in which TiN and Ti/TiHx pairs serve as light absorbers that exhibit strong localized surface plasmon resonance effect with full‐spectrum light absorbance capability. On the other hand, it is theoretically and experimentally demonstrated that the intimate interface between TiH2 and MgH2 can not only thermodynamically and kinetically promote H2 desorption from MgH2 but also simultaneously weaken Ti─H bonds and hence in turn improve H2 desorption from the combination of weakened Ti─H and Ti─H bonds. The uniform integration of photothermal and catalytic effect leads to the direct action of localized heat generated from TiN on initiating the catalytic effect in realizing hydrogen storage of MgH2 with a capacity of 6.1 wt.% under 27 sun. [ABSTRACT FROM AUTHOR]

Magnesium hydride (MgH2) has been recognized as a promising anode material of lithium‐ion batteries (LIBs) owing to its ultrahigh specific capacity. The low conductivity and the structural pulverization induced by large volume expansion, however, has long limited its practical lithium storage performance. Herein, a series of yolk‐shell‐like structures, composed of porous MgH2 nanoparticles (NPs) decorated with Mg‐based composites through in‐situ solid‐gas reaction using MgH2 as both the reactant and the structural template, have been fabricated and uniformly dispersed on electronically conductive graphene. It could not only physically accommodate the volume change of MgH2 owing to the physical protection of Mg‐based composites and the formation of void space inside MgH2 NPs, but also effectively facilitate the transportation of electrons throughout the whole electrode. Particularly, the uniform decoration of ultrathin Mg(BH4)2 as the shell with thermodynamically favorable intercalation of lithium ions and low kinetic barrier for the lithium‐ion diffusion promotes facile transportation of lithium ions into active MgH2, which, coupled with the porous structure constructed by flexible graphene, effectively improves the ion conductivity of the electrode. The synergistic improvement in electronic and ionic conductivity leads to a high reversible capacity of 1651 mAh g−1 at 200 mA g−1 after 380 cycles. [ABSTRACT FROM AUTHOR]

Aluminum–Sulfur (Al–S) batteries are regarded as promising energy storage devices due to their high energy‐to‐price ratios and safety. However, they suffer from clumsy S ↔ Al2S3 reactions and short lifespans that limit their practical application. By combining the merits of adsorptive Cu, catalytic Co, and conductive N‐doped carbon matrix, the bimetals decorated N‐doped carbon (Cu1Co1@NC) enables smooth adsorption and conversion of polysulfides. Consequently, the S@Cu1Co1@NC exhibits excellent electrochemical performance (delivering a high capacity of 317.5 mAh g−1 after 320 cycles at 1.5 A g−1). Moreover, the Cu‐endowed strong Al affinity and robust 3D scaffold with Co‐enhanced conductivity can regulate Al3+ depositing/stripping and successfully suppress Al dendrites. As a result, the Cu1Co1@NC displays negligible Al nucleation overpotential and provides ultra‐long lifespan (>10 000 h) and exceptional reversible (Coulombic efficiency = 99.8–99.9%) Al3+ plating/stripping. Integrating all these advantages, a full Al–S cell constructed with Cu1Co1@NC as two‐in‐one hosts demonstrates excellent capacity retention with enhanced reversibility. This work provides insights into the design of promising Al–S batteries based on bifunctional CuCo bimetal and favorable 3D framework. [ABSTRACT FROM AUTHOR]

The application of Li metal batteries is hindered by the uncontrollable growth of Li dendrites due to the lack of control over Li ion transfer and the formation of solid electrolyte interphase (SEI). Herein, polypropylene (PP) separator modified with acyclic polyaminoborane (PAB, (NH2‐BH2)n) and polyiminoborane (PIB, (NH═BH)n) is developed to regulate electrolyte solvation chemistry and simultaneously facilitate the construction of robust SEI. The mediating effect of PAB and PIB promotes favorable formation of (O)2Li+N to weaken the Li bonds between Li ion and solvent in the electrolyte, which homogenizes Li ion diffusion and reduces the desolvation barrier of Li ions. Additionally, the increase of anions content in the solvation sheath and the reaction between Li metal and PAB and PIB can induce the formation of [LiNBH]n‐enhanced SEI enriched with LiF and Li3N that have Li ion conductivity and mechanical strength to tolerate the volume change of Li metal anode. Therefore, the symmetric cell exhibits a cycling lifetime of over 4000 h. [ABSTRACT FROM AUTHOR]