@article{XU2022, 
author = {Songsong XU and Xiaonan ZHOU and Qiang ZHI and Junjie GAO and Liucheng HAO and Zhongqi SHI and Bo WANG and Jianfeng YANG and Kozo ISHIZAKI},
title = {Anisotropic, biomorphic cellular Si3N4 ceramics with directional well-aligned nanowhisker arrays based on wood-mimetic architectures},
year = {2022},
journal = {Journal of Advanced Ceramics},
volume = {11},
number = {4},
pages = {656-664},
keywords = {silicon nitride, anisotropic, carbothermal reduction nitridation (CRN), wood, nanowhisker arrays},
url = {https://www.sciopen.com/article/10.1007/s40145-021-0555-1},
doi = {10.1007/s40145-021-0555-1},
abstract = {Inspired by the transport behavior of water and ions through the aligned channels in trees, we demonstrate a facile, scalable approach for constructing biomorphic cellular Si3N4 ceramic frameworks with well-aligned nanowhisker arrays on the surface of directionally aligned microchannel alignments. Through a facile Y(NO3)3 solution infiltration into wood-derived carbon preforms and subsequent heat treatment, we can faultlessly duplicate the anisotropic wood architectures into free-standing bulk porous Si3N4 ceramics. Firstly, α-Si3N4 microchannels were synthesized on the surface of CB-templates via carbothermal reduction nitridation (CRN). And then, homogeneous distributed Y-Si-O-N liquid phase on the walls of microchannel facilitated the anisotropic β-Si3N4 grain growth to form nanowhisker arrays. The dense aligned microchannels with low-tortuosity enable excellent load carrying capacity and thermal conduction through the entire materials. As a result, the porous Si3N4 ceramics exhibited an outstanding thermal conductivity (TC, kR ≈ 6.26 W·m-1·K-1), a superior flexural strength (σL ≈ 29.4 MPa), and a relative high anisotropic ratio of TC (kR/kL = 4.1). The orientation dependence of the microstructure-property relations may offer a promising perspective for the fabrication of multifunctional ceramics.}
}