One-step synthesis of hollow urchin-like Ag₂Mn₈O₁₆ for long-life Li-O₂ battery

To solve the critical issues like high polarization and unstable cycle ability, it is vital to design low-cost, stable and efficient catalytic cathode material for nonaqueous Li-O₂ batteries (LOBs). Herein, a hollow urchin-like hollandite Ag₂Mn₈O₁₆ electrocatalyst is fabricated by one-step hydrothermal method. The mixed bimetallic oxide with diverse valences (Mn³⁺ and Mn⁴⁺) and active oxygen defects provide sufficient active sites, and Ag[sbnd]Mn[sbnd]O bonds accelerate charge transformation. LOBs with the well-designed porous Ag₂Mn₈O₁₆ cathode show superior electrochemical performances in LOBs, including ultrahigh specific capacity (7912 mAh g_c⁻¹ at 100 mA g_c⁻¹), good rate performance (5076 mAh g_c⁻¹ at 250 mA g_c⁻¹, 64.16%) and long-term cycle stability (320 cycles at 100 mA g_c⁻¹ within a limited capacity of 250 mAh g_c⁻¹ and 133 cycles at 200 mA g_c⁻¹ within a limited capacity of 500 mAh g_c⁻¹). This work provides a positive effect on designing better catalytic cathode materials for LOBs and push forward the commercialization progress.