Hierarchically Porous and Nitrogen-Rich Carbon Materials Derived from Polyimide Waste for High-Performance Supercapacitor Applications

Abstract

High-performance and eco-friendly carbon electrode material for supercapacitors is still a challenge for both academia and industry. In this work, polyimide waste (PI)-derived, hierarchically porous, and nitrogen-rich carbon materials were prepared by simple hydrothermal treatment and carbonization using potassium hydroxide (KOH) as an activator. The effects of KOH/ preoxidized PI mass ratio and hydrothermal treatment time on the morphology, chemical and crystalline structure, and electrochemical performance were systematically investigated. Interestingly, it is noticed that hydrothermal treatment with KOH solution can promote the infiltration and destruction of preoxidized PI, thereby enhancing the activation effect and forming a hierarchically porous structure. The specific surface area (SSA) of porous carbon with hydrothermal treatment (e.g., PIC 2 -24h) was as high as 2593 m 2 g −1 , which is much larger than that of porous carbon without hydrothermal treatment (PIC 2 ). The as-prepared PIC 2 -24h presented a high specific capacitance of 229 F g −1 at 1 A g −1 , superb rate performance (205 F g −1 at 10 A g −1 ), and excellent cycle stability (94% capacity retention after 20,000 cycles at 1 A g −1 ), revealing that these PI-derived porous carbon materials can not only alleviate the environmental stress caused by the disposal of PI waste but also provide an ideal candidate electrode for high-performance supercapacitor applications.

Activation-Free Synthesis of Chitin-Derived Porous Carbon: Application for Electrical Energy Storage

“…It is speculated that the nitrogen atoms in the CDPCs may have contributed to an increase in pseudocapacitance and/or electrical conductivity. If the capacitances of the CDPCs were enhanced by nitrogen-derived pseudocapacitance, it could lead to an increase in their charge transfer resistances. , On the other hand, if the electrical conductivity of the CDPCs was increased by the nitrogen atoms, their charge transfer and diffusion resistances would be decreased. , Additionally, diffusion resistance is generally reduced by the presence of mesopores. ,, The effect of the electrical conductivity on the charge transfer and diffusion resistances were confirmed by comparing the results of the electrochemical measurements between the 600 and 700 °C heated chitins (Figure S7) and CDPCs (Figure ). The 600 and 700 °C heated chitins did not show pseudocapacitive behavior but showed high charge transfer and diffusion resistances due to their low electrical conductivities.…”

“…74,75 On the other hand, if the electrical conductivity of the CDPCs was increased by the nitrogen atoms, their charge transfer and diffusion resistances would be decreased. 76,77 Additionally, diffusion resistance is generally reduced by the presence of mesopores. 31,78,79 The effect of the electrical conductivity on the charge transfer and diffusion resistances were confirmed by comparing the results of the electrochemical measurements between the 600 and 700 °C heated chitins (Figure S7) and CDPCs (Figure 4).…”

Carbon Nanofibrous Aerogels Derived from Electrospun Polyimide for Multifunctional Piezoresistive Sensors

“…These N substituents facilitate the conductivity of wearable devices, which is crucial for wearable devices to be applied as electronics. 39,40…”

“…Due to its positive charge properties, graphitic-N also increases the conductivity of carbon-based materials. These N substituents facilitate the conductivity of wearable devices, which is crucial for wearable devices to be applied as electronics. , …”

Advancements in Synthesis Strategies and Optoelectronic Applications of Bio-Based Photosensitive Polyimides

“…Polyimide, due to its excellent comprehensive performance, such as high thermal stability [1,2], mechanical strength [3,4], chemical resistance [5,6], dielectric properties [7,8], and biocompatibility [9][10][11], is widely used in microelectronics [12,13], sensors [14][15][16], energy storage [17][18][19], biomedical engineering [20][21][22], aerospace [23,24], and other industries. In particular, photosensitive polyimide, as a unique high-performance polymer, has both the function of photoresisting and can be used as a dielectric insulation layer [25].…”