Thermal chemical vapor deposition split-functionalizing processes, coatings, and products are disclosed. The thermal chemical vapor deposition split-functionalizing process includes positioning an article within an enclosed chamber, functionalizing the article within a first temperature range for a first period of time, and then further functionalizing the article within a second temperature range for a second period of time. The thermal chemical vapor deposition split-functionalized product includes a functionalization formed by functionalizing within a first temperature range for a first period of time and a further functionalization formed by further functionalizing within a second temperature range for a second period of time.