A coin like porous carbon derived from Al-MOF with enhanced hierarchical structure for fast charging and super long cycle energy storage

Abstract

A coin-shaped porous carbon is produced by carbonization of Al-based metal-organic frameworks and followed by the removal of Al2O3 though dissolving in NaOH solution. The hierarchically porous carbon has a large surface area (1,508 m2 g−1) with suitable size of mesopores (6.35 nm). The material exhibits an increased specific capacitance of 323 F g−1 at 1 mV s−1. It also has excellent high current discharge performance and superior stability with 97.9% retention at an ultra-high current density of 100 A g−1 during 15 × 104 cycles. The constructed symmetric solid supercapacitor shows an appreciably large capacitance of up to 117.2 F g−1 at 0.2 A g−1, corresponding to the high energy density of 36.5 W h kg−1 within a voltage window of 1.5 V. In addition, it offers satisfied durability with 11.5% decay rate after 20,000 cycles. The carbon with improved electrochemical properties is most likely attributed to its special coin shape and hierarchically porous pores. It is a new potential strategy to configure unique structure porous carbon materials for power supercapacitors via metal-organic frameworks serving as precursors.