CHEMICALLY TURNABLE POROUS SI SENSORS FOR IN SITU MONITORING OF TOXINS

光致发光发出的光的颜色和强度 多孔硅可以通过化学吸附进行改性。例如，当 多孔硅暴露在致癌物质苯的蒸气中，其 发光强度下降50%以上。这种影响是可逆的， 所以当化学物质蒸发时，原来的强度 发光被恢复了。多种多环芳烃会影响 多孔硅以类似的方式。此属性演示 多孔硅在气体或液体传感器中应用的可行性。学生们 参与提议的项目将量化多孔洞的反应 硅向多芳烃、一氧化碳、一氧化氮、 二氧化碳和重金属，以确定潜在的 这种材料可以作为生物相关物质的传感器 化学制品。

The color and intensity of the light given off from photoluminescent porous silicon can be modified by chemical adsorbates. For example, when porous silicon is exposed to vapors of the carcinogen benzene, its luminescence intensity drops by more than 50%. The effect is reversible, so when the chemical evaporates off, the original intensity of the luminescence is recovered. A variety of polyaromatic hydrocarbons affect porous silicon in a similar fashion. This property demonstrates the feasibility of using porous Si in gas or liquid sensors. The students involved in the proposed project will quantify the response of porous silicon toward polyaromatic hydrocarbons, carbon monoxide, nitric oxide, carbon dioxide, and heavy metals, in order to define the potential for this material to act as a sensor for these biologically relevant chemicals.