Acta Phys. -Chim. Sin. ›› 2026, Vol. 42 ›› Issue (10): 100333.doi: 10.1016/j.actphy.2026.100333

• ARTICLE • Previous Articles     Next Articles

Biomimetic "fibrous root systems" in phase-change composites for photothermal conversion and energy storage

Jie Fu1, Linghan Bai3,*(), Liqiu Chu1, Hanyu Zou2, Long Qin2, Shuxin Jia5, Meile Ni6, Zhifan Hao7,*(), Mengxiao Sun4,*(), Fan Wu2,*()   

  1. 1 Sinopec Beijing Research Institute of Chemical Industry, Beijing 100013, China
    2 Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
    3 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
    4 School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, China
    5 School of Life Sciences, Qilu Normal University, Jinan 250000, Shandong Province, China
    6 College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, Shaanxi Province, China
    7 Research Department of Resources and Chemicals, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2026-03-25 Revised:2026-05-22 Accepted:2026-05-27 Published:2026-09-03
  • Contact: wufan0817@tju.edu.cn (Fan Wu)Email: LinghanBAi@ustb.edu.cn (Linghan Bai)hzf2112@xs.ustb.edu.cn (Zhifan Hao)smx20231002@hebut.edu.cn (Mengxiao Sun)

Abstract:

Phase change materials (PCMs) with efficient photothermal conversion and energy storage capabilities show great potential in the capture, conversion, and storage of solar energy. However, although pristine PCMs possess high latent heat, they suffer from issues such as low efficiency in light capture and absorption, poor thermal conductivity, phase leakage, and poor shape stability. Therefore, by integrating PCMs with photothermal conversion materials and inspired by the "root hair" structure of plants, we designed a novel biomimetic phase change material. This material employs a dual-carbon structure composed of carbonized PBO fiber (CPF) and in-situ generated nickel nanoparticles (NPs) confined within carbon nanotubes (CNTs), denoted as CPF@Ni/CNTs, as a three-dimensional porous carbon skeleton support. Using nickel nanoparticles as functional fillers and paraffin wax (PW) as the phase change material, the PW-CPF@Ni/CNTs composite PCM was successfully fabricated. Benefiting from the physical adsorption of the 3D network porous structure, a high PW loading ratio of 254% was achieved, and leakage was effectively suppressed during phase change (leakage rate ≤ 0.17% after 300 thermal cycles). The introduction of nickel nanoparticles not only constructed abundant thermal conduction pathways, but also, through the synergistic effect of localized surface plasmon resonance (LSPR) and the graphitized carbon structure with high broadband light absorption, significantly enhanced the light capture and energy conversion efficiency of the composite PCM. Consequently, the PW-CPF@Ni/CNTs composite PCM exhibited a latent heat of 183.6 J g−1, a thermal conductivity of 0.77 W (m K)−1 (2.6 times higher than pure PW), and a photothermal conversion efficiency of 96.69% (100 mW cm−2). Furthermore, the composite PCM maintained excellent thermal reliability after 300 photothermal cycles. This study proposes a novel biomimetic root-hair-like nickel-induced dual-carbon 3D network porous structure for the controlled fabrication of multifunctional, high-performance composite PCMs and provides a detailed analysis of their photothermal conversion mechanism. This new composite PCM holds significant application potential in solar energy storage, solar water heating, and thermal management of electronic devices.

Key words: Phase change materials, Photothermal conversion, Thermal energy storage, Fibrous network, Carbon nanotube