Electrochemical oxygen reduction reaction (ORR) for hydrogen peroxide (H₂O₂) synthesis offers a sustainable alternative to the anthraquinone process, yet suffers from inherent activity–selectivity tradeoffs. Herein, this work addresses this challenge through the incorporation of Mo into CeO₂ (Mo-CeO₂) featuring oxygen vacancy-mediated Mo–Ce dual-active sites. Mo incorporation into CeO₂ lattice through hydrothermal defect engineering simultaneously elevates oxygen vacancy concentration and induces localized electron redistribution, creating synergistic sites where Mo atoms facilitate proton donation via spontaneous water dissociation while adjacent Ce centers optimize O₂ adsorption configurations to enhance the intrinsic activity of H₂O₂ generation. In-situ characterization and density functional theory calculations reveal that the unique hollow adsorption geometry stabilizes *OOH intermediates and decouples conventional scaling relationships between O₂ adsorption and intermediate binding. This atomic-level cooperativity enables an unprecedented H₂O₂ selectivity of 93%, H₂O₂ yield of 8.2 mol·g_cat⁻¹·h⁻¹ at 100 mA·cm⁻², and exceptional stability. The study establishes an efficient design principle for transition metal oxide catalysts in multi-electron transformations, demonstrating how dual-site engineering can simultaneously enhance intermediate stabilization and reaction kinetics for sustainable electrosynthesis applications.

MXene is a promising electrode material for supercapacitors due to its excellent conductivity, but its self-stacking impedes ion and electron transport. To address this issue, CNTs were introduced as conductive spacers, and NiCo-LDH was rapidly deposited via an assisted liquid-phase plasma electrolysis method to construct a stable heterostructure. This design effectively alleviates ion/electron transport resistance, improves charge transfer efficiency, and mitigates the volume expansion of NiCo-LDH during cycling. Density functional theory analysis reveals enhanced electronic conductivity and ion migration at the MXene/CNT/NiCo-LDH heterointerface. Benefiting from the synergistic structure, the electrode achieves a high specific capacitance of 2145 F g^-1 and maintains 95.2% of its initial capacitance after 5000 cycles. The assembled asymmetric supercapacitor delivers an energy density of 41.9 Wh kg^-1 at 425.1 W kg^-1 and retains 91% of capacitance after 5000 cycles. Moreover, the flexible device exhibits remarkable stability under multiple bending angles without distortion of CV curves.

MgH₂ is considered one of the most promising hydrogen storage materials because of its safety, high efficiency, high hydrogen storage quantity and low cost characteristics. But some shortcomings are still existed: high operating temperature and poor hydrogen absorption dynamics, which limit its application. Porous Ni₃ZnC_0.7/Ni loaded carbon nanotubes microspheres (NZC/Ni@CNT) is prepared by facile filtration and calcination method. Then the different amount of NZC/Ni@CNT (2.5, 5.0 and 7.5 wt%) is added to the MgH₂ by ball milling. Among the three samples with different amount of NZC/Ni@CNT (2.5, 5.0 and 7.5 wt%), the MgH₂-5 wt% NZC/Ni@CNT composite exhibits the best hydrogen storage performances. After testing, the MgH₂-5 wt% NZC/Ni@CNT begins to release hydrogen at around 110 ℃ and hydrogen absorption capacity reaches 2.34 wt% H₂ at 80 ℃ within 60 min. Moreover, the composite can release about 5.36 wt% H₂ at 300 ℃. In addition, hydrogen absorption and desorption activation energies of the MgH₂-5 wt% NZC/Ni@CNT composite are reduced to 37.28 and 84.22 KJ/mol H₂, respectively. The in situ generated Mg₂NiH₄/Mg₂Ni can serve as a “hydrogen pump” that plays the main role in providing more activation sites and hydrogen diffusion channels which promotes H₂ dissociation during hydrogen absorption process. In addition, the evenly dispersed Zn and MgZn₂ in Mg and MgH₂ could provide sites for Mg/MgH₂ nucleation and hydrogen diffusion channel. This attempt clearly proved that the bimetallic carbide Ni₃ZnC_0.7 is a effective additive for the hydrogen storage performances modification of MgH₂, and the facile synthesis of the Ni₃ZnC_0.7/Ni@CNT can provide directions of better designing high performance carbide catalysts for improving MgH₂.