等离子体刻蚀并沉积类金刚石膜制备超疏水木材

为使木材表面具备疏水性能,采用等离子体刻蚀并沉积亲水性类金刚石(DLC)薄膜的方法对糖枫木(Acer saccharum)进行表面改性研究,通过扫描电子显微镜(SEM)、激光扫描共聚焦显微镜(LSCM)、接触角测量仪、椭圆偏振光谱仪、X-射线光电子能谱仪(XPS),分析和表征了处理前后木材表面的微观形貌、粗糙度、润湿性能、沉积薄膜的厚度及元素组成和化学状态。结果表明:刻蚀时间小于30 min时,木材表面的平均粗糙度、均方根光洁度和高低差均随着刻蚀时间的延长逐渐增大; 当刻蚀时间延长至45 min时,表面的粗糙度略有减小。木材表面的接触角随着刻蚀时间的延长先增大后减小,当刻蚀30 min并沉积DLC薄膜1.5 min时,接触角最大可达157.2°; 而延长刻蚀时间至45 min时,其接触角为152.3°。相同的刻蚀时间下,木材表面的接触角随着DLC薄膜沉积时间的延长逐渐减小。通过计算,DLC薄膜的沉积速率为(51.7±4.5)nm/min; 沉积DLC薄膜后,表面氧元素的含量明显减少,出现了石墨特征峰sp2-C和金刚石特征峰sp3-C。
This study presents the fabrication of superhydrophobic wood of Acer saccharum Marsh. using a combination of O2 plasma etching and plasma deposition of a thin hydrophilic diamond-like carbon(DLC)coating in order to impart wood with controlled wetting properties. The effect of O2 plasma etching on roughness was investigated using the scanning electron microscopy(SEM)and laser scanning confocal microscope(LSCM)profilometry. The wetting behavior was determined by the static water contact angle measurement. Furthermore, the morphology, thickness of deposited films, element composition and their chemical bonding information of the wood surfaces before and after the treatment were also examined with SEM, the ellipsometer and X-ray photoelectron spectroscopy(XPS). The results showed that the wood surfaces of the average roughness, root mean square roughness and peak-to-valley roughness increased with longer etching time within 30 min. However, the wood surface roughness decreased slightly after the prolonged etching time of 45 min. The static water contact angles of the wood surface increased firstly and then decreased with the increase of etching time and attained a maximum value for 157.2° with 30 min etching and after depositing DLC film for 1.5 min, but the static water contact angle of the wood surface etched for 45 min and after depositing DLC film for the same time was 152.3°. The static water contact angles decreased gradually with an increase in deposition times if the wood surfaces were subjected to the same time etching. From the data of the deposition thickness, the deposition rate of DLC films was calculated, which was constant(51.7±4.5)nm/min over the deposition times investigated. The content of oxygen element reduced obviously and the diamond-like characteristic peaks of sp2-C and sp3-C presented after the wood surfaces deposited with the DLC film coating