To explore recycling solutions for used lithium-ion batteries (LIBs), a tribocatalytic method is proposed in this paper. When ZnO nanoparticles were used as catalysts, the leaching rates of lithium and cobalt in lithium cobaltate batteries reached 95% and 84%, respectively. In Li–Co–Mn–Ni batteries, the leaching rates of lithium, cobalt, manganese, and nickel were 96.61%, 90.00%, 76.06%, and 61.78%, respectively. In the acid leaching system, the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) of citric acid (CA) were in more appropriate positions, indicating that CA is more prone to redox reactions when rubbed on the surface of zinc oxide. Compared with H₂O, CA is more electrostatically polarized and can participate in more reactions through electron transfer on the ZnO surface. First-principles calculations of the adsorption energies show that the interactions are stronger when CA molecules are located on the lithium cobalt oxide (LCO)(110) surface. The combination of theoretical calculations and experiments verified that the tribocatalytic weak acid leaching process is an effective ion leaching scheme. The free radicals generated during the catalytic process promoted the leaching of metal ions, thus enabling the recycling of cathode materials for lithium-ion batteries. In addition, this method has great potential for the reduction and leaching of ions.

Combining layers with high breakdown resistance and high polarization is a promising approach for designing dielectric capacitors with high energy density and efficiency. However, such combinations often accompany strong interfacial polarization, magnification of local electric fields, leading to premature breakdown. This work addresses this issue via controlled formation of diffusospheres. We constructed multilayer heterogeneous films using two Bi_0.5Na_0.5TiO₃ (BNT)-based substances with high breakdown resistance and high polarization properties. Experimental results and finite element simulations demonstrate that the energy storage capacity of these films effectively harnesses the advantages of both phases. Notably, the interface polarization is minimal. Instead, a solid solution-like diffusosphere, formed by the mutual diffusion of ions between the two phases, plays a crucial role. The diffusosphere acts as a transition zone, mitigating charge aggregation at the interfaces and optimizing the relaxor and breakdown characteristics of the capacitor. With six diffusospheres, the multilayer heterogeneous capacitor achieves a recoverable energy storage density of 94 J/cm³, a significant advancement in BNT-based energy storage films. This work proposes and validates the concept of diffusospheres and their role in reducing interfacial polarization in multilayer heterogeneous films, enhancing the understanding of heterogeneous composite structures and advancing the field of dielectric energy storage.

The rapidly advancing energy storage performance of dielectric ceramics capacitors has garnered significant interest for applications in fast charge/discharge and high-power electronic techniques. Exploring the exceptional electrical properties in harsh environments can further promote their practical applications. Defect carriers can be excited under luminance irradiation, thereby leading to degradation of energy storage performance. Herein, a synergic optimization strategy is proposed to enhance energy storage properties and luminance resistance of (K_0.5Na_0.5)NbO₃-base (KNN) ceramics. First, the introduction of Bi(Zn_0.5Ti_0.5)O₃ solid solution and La³⁺ ions disrupts the long-range polar orders and enhances super paraelectric relaxation characteristics. Additionally, doping La³⁺ ions can increase the band gap and reduce oxygen vacancy concentration, resulting in excellent luminance resistance. Finally, the viscous polymer process is employed to suppress the grain growth and promote chemical homogeneity. As a result, ultrahigh recoverable energy storage density (W_rec) of 8.11 J/cm³ and high efficiency (η) of 80.98% are achieved under an electric field of 568 kV/cm. Moreover, the variations in W_rec and η are only 12.45% and 1.75%, respectively, under 500 W xenon lamp irradiation compared to the performance under a dark environment. These findings hold great potential in facilitating the practical application of dielectric ceramic capacitors in luminance irradiation environments.