Surfactant assisted synthesis of strontium hexaferrite microspheres for the fabrication of high-performance asymmetric supercapacitors

Abstract

In this work, we describe a surfactant-assisted chemical co-precipitation methodology for the synthesis of strontium hexaferrite (SrFe₁₂O₁₉). Various physicochemical techniques were used to confirm the formation of SrFe₁₂O₁₉ particles. XRD and SEM analyses confirmed the formation of M-type strontium hexaferrite spheres. The as-prepared SrFe₁₂O₁₉ particles were utilized as an electrode material in supercapacitors. As a result, SrFe₁₂O₁₉ delivered a maximum specific capacity (C_sp) of 1085 C g⁻¹ at 1 A g⁻¹, and retained 96.0% of its specific capacity even after 6000 GCD cycles. As a consequence, the SrFe₁₂O₁₉ sample was used to construct an asymmetric SrFe₁₂O₁₉//AC device, which exhibited an energy density of 13.8 W h kg⁻¹ at a power density of 496.8 W kg⁻¹. The unique structural features and multiple redox sites and increased electrical conductivity of SrFe₁₂O₁₉ are responsible for its excellent capacity behavior. Thus, it is clear that SrFe₁₂O₁₉ microspheres can be exploited as an electrode material in high-performance supercapacitor devices for real-time applications.