(a) As-spun and posttwisted small-diameter CNT fibers spun form a 650 μm array. (b) A comparison of fiber strengths at different array heights. The black line shows that the strength of CNT fibers increases with the array height, and marks shows the strength dependence on array morphology (the dot represents the data from oxygen-assisted growth that shows poor CNT alignment, the square represents the data from the normal growth, and the triangle represents the data from the hydrogen-assisted growth that shows good CNT alignment) [10, 12].
