Figure 11.

Reported power density of TENGs with surface modification methods over publication year. Each data point is taken from the following references: surface patterning,^116−119 mechanical morphology control,^{114,120−125} laser treatment,^126−128 plasma treatment,¹²⁹ nano fiber,^132−134 ion doping,^135,137 chemical functional group,¹³⁸ and nano composite embedding^141,143