Professor Kim Mi-so’s research team from the School of Advanced Materials Science and Engineering has developed a piezoelectric selfpowered motion sensor using atmospheric moisture. Piezoelectric polymer fiber, piezoelectric material that produces electricity by mechanical transformation, is leadfree and flexible, which emerges as applications for biomedical and wearable sensors. The research team focused on the structural aspect of the piezoelectric property and presented that the control of structure can enhance the piezoelectric self-powered sensor capacity. The team successfully produced the polymeric piezoelectric fiber by combining electrospinning to fabricate piezoelectric fibers with the porous surface under ambient humidity. The piezoelectric fiber with surface porosity enabled the self-powered motion sensor to actualize with outstanding voltage and power performance. Prof. Kim said, “It is meaningful to develop and retain the method of fabricating the piezoelectric fibers with higher surface porosity using the humidity, which enhances the sensor capacity.” This study was recently published online in the international journal Small and was presented on the journal cover page.