Assembly of N- and P-functionalized carbon nanostructures derived from precursor-defined ternary copolymers for high-capacity lithium-ion batteries

• Published in: Chinese journal of chemical engineering 2023-01, Vol.53 (1), p.280-288
• Main Authors: Guo, Luyao, Wang, Mengru, Lin, Ronghe, Ma, Jiaxin, Zheng, Shuanghao, Mou, Xiaoling, Zhang, Jun, Wu, Zhong-Shuai, Ding, Yunjie
• Format: Article
• Language: English
• Subjects: Carbon nanospheres; Doping; Lithium-ion batteries; Polymers; Porosity
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/j.cjche.2022.01.032

[Display omitted] Synthesis of new carbon nanostructures with tunable properties is vital for precisely regulating electrochemical performance in the wide applications. Herein, we report a novel approach for the oxidative polymerization of N- and P-bearing copolymers from the self-assembly of three different monomers (aniline, pyrrole, and phytic acid), and further prepare the respective carbon nanostructures with relatively consistent N dopant (6.2%–8.0%, atom) and varying P concentrations (0.4%–2.8%, atom) via controllable pyrolysis. The impacts of phytic acid addition on the compositional, structural, and morphological evolution of the copolymers and the resulting nanocarbons are well studied through a spectrum of characterizations including N2 sorption, Fourier transform infrared spectroscopy, gel permeation chromatograph, scanning/transmission electron microscopy, and X-ray photoelectron spectroscopy. Gradual fragmentation of the nanosphere structures is evidenced with increasing addition of phytic acid, leading to different nanostructures from hollow nanospheres to 3D aggregates. Nanocarbons decorated with N and P dopants from pyrolysis are further utilized as anode materials in lithium-ion batteries, demonstrating enhanced electrochemical performance, i.e., a reversible capacity of 380 mA·h·g−1 at 2 A·g−1 for NPC-0.5 during 200 cycles. The superior performance originates from the balanced porosity, and appropriate concentrations of P and pyrrolic N, thus pointing the direction for designing high-performance anode materials.