Wang Xianlong, Fu Fangbao, Zhang Wenli, Wen Jiale, Qiu Xueqing
School of Chemical Engineering and Light Industry, Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
School of Chemical Engineering and Light Industry, Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, Guangdong, China; Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China; Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Guangdong University of Technology, Guangzhou 510006, China.
J Colloid Interface Sci. 2025 Dec 15;700(Pt 2):138466. doi: 10.1016/j.jcis.2025.138466. Epub 2025 Jul 16.
Carbon/transition metal oxide composites hold significant promise for energy storage applications; however, achieving precise control over the carbon structure to enhance the electrochemical activity of metal oxides remains a challenge. In this work, we utilized low-cost enzymatic lignin as a carbon source and harnessed the synergistic effects of magnesium oxide templates and potassium acetate activator to synthesize a lignin-derived hierarchical porous carbon (HPLC) characterized by a high specific surface area of 1704 ± 36 m/g, well-ordered nanosheet structures, and hierarchical porosity. The comparative analysis demonstrated that HPLC exhibited superior pore anchoring and enhanced interfacial Mn-O-C bonding interactions with manganese dioxide compared to mesoporous carbon synthesized via magnesium oxide templating and microporous carbon derived from potassium acetate activation. This unique architecture significantly boosted the charge storage capacity of manganese dioxide. The composite showed remarkable electrochemical performance, achieving a specific capacitance of up to 567 F/g at a current density of 0.5 A/g, while also demonstrating excellent rate capability. An asymmetric capacitor constructed with the composite electrode delivered a high energy density of 47.22 Wh/kg and maintained a capacity retention of 85.2 % after 12,000 cycles at 2.0 A/g, illustrating its outstanding cycling stability. Analysis of the energy storage mechanism revealed that the capacity of this material was predominantly attributed to redox reactions involving manganese species induced by potassium ion insertion and extraction, as well as the double-layer capacitance arising from the adsorption and desorption of potassium ions. This work elucidates the crucial influence of carbon structure on the loading of metal oxides, providing a novel strategy for tuning carbon carrier structures aimed at developing high-performance carbon/metal composites.
碳/过渡金属氧化物复合材料在储能应用方面具有巨大潜力；然而，精确控制碳结构以增强金属氧化物的电化学活性仍然是一项挑战。在这项工作中，我们利用低成本的酶解木质素作为碳源，并借助氧化镁模板和醋酸钾活化剂的协同作用，合成了一种木质素衍生的分级多孔碳（HPLC），其具有1704±36 m²/g的高比表面积、有序的纳米片结构和分级孔隙率。对比分析表明，与通过氧化镁模板法合成的介孔碳和由醋酸钾活化得到的微孔碳相比，HPLC对二氧化锰表现出优异的孔锚定作用，并增强了界面Mn-O-C键合相互作用。这种独特的结构显著提高了二氧化锰的电荷存储容量。该复合材料表现出卓越的电化学性能，在0.5 A/g的电流密度下实现了高达567 F/g的比电容，同时还展现出优异的倍率性能。用该复合电极构建的不对称电容器在2.0 A/g的电流密度下循环12000次后，具有47.22 Wh/kg的高能量密度，并保持85.2%的容量保持率，说明了其出色的循环稳定性。对储能机制的分析表明，这种材料的容量主要归因于钾离子插入和脱出诱导的涉及锰物种的氧化还原反应，以及钾离子吸附和解吸产生的双电层电容。这项工作阐明了碳结构对金属氧化物负载的关键影响，为调整碳载体结构以开发高性能碳/金属复合材料提供了一种新策略。
