超轻、高强的三维碳化硅结构

Ultralight, Strong, Three-Dimensional SiC Structures.

机构信息

College of Engineering, Mathematics and Physical Sciences, University of Exeter , Exeter EX4 4QF, U.K.

Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London , London SW7 2AZ, U.K.

出版信息

ACS Nano. 2016 Feb 23;10(2):1871-6. doi: 10.1021/acsnano.5b05533. Epub 2015 Nov 23.

DOI:10.1021/acsnano.5b05533

PMID:26580985

Abstract

Ultralight and strong three-dimensional (3D) silicon carbide (SiC) structures have been generated by the carbothermal reduction of SiO with a graphene foam (GF). The resulting SiC foams have an average height of 2 mm and density ranging between 9 and 17 mg cm(-3). They are the lightest reported SiC structures. They consist of hollow struts made from ultrathin SiC flakes and long 1D SiC nanowires growing from the trusses, edges, and defect sites between layers. AFM results revealed an average flake thickness of 2-3 nm and lateral size of 2 μm. In-situ compression tests in the scanning electron microscope (SEM) show that, compared with most of the existing lightweight foams, the present 3D SiC exhibited superior compression strengths and significant recovery after compression strains of about 70%.

摘要

通过 SiO 与石墨烯泡沫（GF）的碳热还原，生成了超轻和高强度的三维（3D）碳化硅（SiC）结构。所得 SiC 泡沫的平均高度为 2 毫米，密度在 9 至 17 毫克/立方厘米之间。它们是报道的最轻的 SiC 结构。它们由超薄片碳化硅薄片组成的空心支柱和从桁架、边缘和层之间的缺陷部位生长的长 1D SiC 纳米线组成。原子力显微镜（AFM）结果显示平均薄片厚度为 2-3nm，横向尺寸为 2μm。在扫描电子显微镜（SEM）中的原位压缩测试表明，与大多数现有的轻质泡沫相比，本 3D SiC 表现出更高的压缩强度和在压缩应变约 70%后的显著恢复。