Enabling Wasted A4 Papers as a Promising Carbon Source to Construct Partially Graphitic Hierarchical Porous Carbon for High-Performance Aqueous Zn-Ion Storage

Abstract

Considering the superiorities of abundance, easy collection, low cost, and nearly constant composition, the wasted A4 papers are deemed as a recyclable and scalable carbon source to fabricate functional carbon materials for Zn-ion hybrid supercapacitors (ZIHSCs), which integrate the supercapacitors' highpower output and batteries' high energy density. Herein, the wasted A4 papers are efficiently converted into an advanced carbon material owning a hierarchical porous structure with a high surface area and interconnected multiscale channels, a graphitic structure, and a good level of N/O codoping. By taking advantage of these features, an express electron/ion transfer pathway, a large accessible surface interface, and a robust architecture are achieved for swift kinetics, numerous active sites, and excellent steadiness to afford a charming Zn 2+ storage capability for the aqueous coin-type ZIHSC device (a high capacity of 244 mAh g −1 at 0.1 A g −1 with a capacity conservation of 116.4 mAh g −1 even amplifying the current density by 200 times, a supreme energy density of 190.4 Wh kg −1 , a supreme power output of 18 kW kg −1 , and an eminent durability of 93.8% over 10,000 cycles at 10 A g −1 ). Excitingly, the quasi-solid ZIHSC device also bespeaks an enjoyable capacity of 211.7 mAh g −1 , a high energy density of 159.3 Wh kg −1 , good mechanical flexibility, and a low self-discharge rate. This work puts forward a simple and scalable strategy to enable the wasted A4 paper as a competitive carbon source to construct advanced cathode material for Zn 2+ storage.

Biomass-Derived Carbon Materials for Advanced Metal-Ion Hybrid Supercapacitors: A Step Towards More Sustainable Energy

“…MIHSCs are a hybrid of supercapacitors and batteries, with both the high power density of supercapacitors and the high energy density of batteries. Li et al [10] explained that by incorporating supercapacitor-type and battery-type electrodes, MIHSCs inherit two charge storage mechanisms, delivering a high level of power per unit volume from the supercapacitor and a high level of energy per unit volume from the battery. In other words, MIHSCs are vital in maintaining modern devices due to their acutely growing energy demands.…”