Preparation of three-dimensionally hierarchical porous carbons (HPCs) with biomass wastes for high-performance supercapacitors has being the hotspot subject in the past decade from sustainable and renewable points of view. In this paper, an industrial biomass waste of beet pulp (BP) is used as precursor to purposely prepared N/P/O co-doped HPCs by a simple yet efficient two-step method. Another industrial solid waste of fly ash (FA), containing inorganic oxides (mainly SiO₂, Al₂O₃, Fe₂O₃, and CaO) with varied sizes, is utilized as the ingredient acting as pore-forming template to regulate the morphology and increase the porosity of the resulting HPCs (derived from BP and FA, which are designated as BFCs). The optimal sample of BFC-2 exhibits an exceptionally high specific capacitance up to 522.1 F g⁻¹ at 1.0 A g⁻¹ in 6 M KOH electrolyte. Furthermore, the symmetric supercapacitor assembled with BFC-2 can deliver large energy densities in both 1 M Na₂SO₄ (39.3 Wh kg⁻¹) and EMIMBF₄ (97.9 Wh kg⁻¹) with satisfactory rate retentions, as well as prominent cycling durabilities. These exciting results show a low-cost, environmentally benign, and waste profitable idea to prepare HPCs for high-performance supercapacitors, which is in good accordance with the principle of " changing waste into wealth " in the green energy resources.

从可持续和可再生的角度来看，过去十年来，利用生物质废物制备用于高性能超级电容器的三维分层多孔碳（HPC）一直是热门话题。在本文中，通过简单而有效的两步法，将甜菜粕的工业生物质废料（BP）用作特制N / P / O共掺杂HPC的前体。粉煤灰（FA）的另一种工业固体废物，其中含有无机氧化物（主要为SiO ₂，Al ₂ O ₃，Fe ₂ O ₃各种尺寸的CaO（和CaO）用作成孔模板，以调节所得HPC（衍生自BP和FA，称为BFC）的形态并增加其孔隙率。在6 M KOH电解质中，BFC-2的最佳样品在1.0 A g ^-1下显示出高达522.1 F g ^-1的极高比电容。此外，与BFC-2组装的对称超级电容器可以在1 M Na ₂ SO ₄（39.3 Wh kg ^-1）和EMIMBF ₄（97.9 Wh kg ^-1）中提供较大的能量密度。），具有令人满意的保费率，以及出色的骑行耐久性。这些令人振奋的结果表明，低成本，环保，浪费的想法可以为高性能超级电容器准备高性能计算，这完全符合绿色能源中“变废为宝”的原则。