Advanced Corrosion Resistant Materials for Electrochemical Applications

等离子体辅助化学气相沉积（PACVD）沉积金刚石薄膜是美国、日本和苏联正在追求的一个迅速发展的技术领域。金刚石薄膜具有独特的化学和物理性能，如抗氧化性和硬度。通过PACVD生长的掺硼金刚石薄膜的电阻率接近1欧姆-厘米。在钨基板上已经沉积了厚度小于1微米的无孔粘附薄膜。本研究的目的是评估这些薄膜作为磷酸燃料电池（PAFC）双极分离板（碳-碳复合材料）的导电、耐腐蚀涂层。目前的板设计失败是因为碳填料的腐蚀和酸被板吸收，最终导致电池的支撑。沉积在双极板上的金刚石薄膜，除了具有耐腐蚀性外，还可以作为阻隔层，从而防止酸的吸收。

Deposition of thin diamond films by plasma assisted chemical vapor deposition (PACVD) is a rapidly emerging area of technology being pursued in The United States, Japan and the Soviet Union. Diamond films have unique chemical and physical properties such as oxidation resistance and hardness. Boron-doped diamond films grown by PACVD can have electrical resistivities approaching 1 ohm-cm. Pore-free, adherent films of less than 1-micron thickness have already been deposited on tungsten substrates. The goal of this study is to evaluate these films as an electrically conductive, corrosion-resistant coating for bipolar separator plates (carbon-carbon composites) in phosphoric acid fuel cells (PAFC). Present plate designs fail because of corrosion of the carbon filler and acid absorption by the plate which leads to eventual shoring of the cell. Thin diamond films deposited on the bipolar plates, in addition to being corrosion resistant, can also act as a barrier layer, thus preventing acid absorption.