Zhao Lei, Sun Shirong, Lin Jinxin, Zhong Lei, Chen Liheng, Guo Jing, Yin Jian, Alshareef Husam N, Qiu Xueqing, Zhang Wenli
Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, School of Chemical Engineering and Light Industry, Guangdong University of Technology (GDUT), 100 Waihuan Xi Road, Panyu District, Guangzhou, 510006, People's Republic of China.
Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao, 066004, People's Republic of China.
Nanomicro Lett. 2023 Jan 27;15(1):41. doi: 10.1007/s40820-022-01006-0.
Amorphous carbons are promising anodes for high-rate potassium-ion batteries. Most low-temperature annealed amorphous carbons display unsatisfactory capacities. Heteroatom-induced defect engineering of amorphous carbons could enhance their reversible capacities. Nevertheless, most lignocellulose biomasses lack heteroatoms, making it a challenge to design highly heteroatom-doped carbons (> 10 at%). Herein, we report a new preparation strategy for amorphous carbon anodes. Nitrogen/sulfur co-doped lignin-derived porous carbons (NSLPC) with ultra-high nitrogen doping levels (21.6 at% of N and 0.8 at% of S) from renewable lignin biomacromolecule precursors were prepared through a supramolecule-mediated pyrolysis strategy. This supermolecule/lignin composite decomposes forming a covalently bonded graphitic carbon/amorphous carbon intermediate product, which induces the formation of high heteroatom doping in the obtained NSLPC. This unique pyrolysis chemistry and high heteroatom doping of NSLPC enable abundant defective active sites for the adsorption of K and improved kinetics. The NSLPC anode delivered a high reversible capacity of 419 mAh g and superior cycling stability (capacity retention of 96.6% at 1 A g for 1000 cycles). Potassium-ion hybrid capacitors assembled by NSLPC anode exhibited excellent cycling stability (91% capacity retention for 2000 cycles) and a high energy density of 71 Wh kg at a power density of 92 W kg.
非晶碳是用于高倍率钾离子电池的有前景的阳极材料。大多数低温退火的非晶碳表现出不尽人意的容量。非晶碳的杂原子诱导缺陷工程可以提高其可逆容量。然而，大多数木质纤维素生物质缺乏杂原子，这使得设计高杂原子掺杂的碳（>10原子%）具有挑战性。在此，我们报道了一种非晶碳阳极的新制备策略。通过超分子介导的热解策略，从可再生木质素生物大分子前体制备了具有超高氮掺杂水平（21.6原子%的N和0.8原子%的S）的氮/硫共掺杂木质素衍生多孔碳（NSLPC）。这种超分子/木质素复合材料分解形成共价键合的石墨碳/非晶碳中间产物，这诱导了所得NSLPC中高杂原子掺杂的形成。NSLPC这种独特的热解化学和高杂原子掺杂为钾的吸附提供了丰富的缺陷活性位点并改善了动力学。NSLPC阳极提供了419 mAh g的高可逆容量和优异的循环稳定性（在1 A g下循环1000次，容量保持率为96.6%）。由NSLPC阳极组装的钾离子混合电容器表现出优异的循环稳定性（2000次循环后容量保持率为91%），在功率密度为92 W kg时具有71 Wh kg的高能量密度。
