Wearable and sensitive heart-rate detectors based on PbS quantum dot and multiwalled carbon nanotube blend film

Wearable and sensitive photodetectors (PDs) have been demonstrated based on a blend film of PbS quantum dots (QDs) and QDs modified multiwalled carbon nanotubes (MWCNTs). Owing to the synergetic effect from high light sensitivity of PbS QDs and excellent conductive and mechanical properties of MWCNTs, the blend PDs show high sensitivity and flexibility performance: device responsivity and detectivity reach 583 mA/W and 3.25 x 10(12) Jones, respectively, and could stand large number (at least 10 000 cycles) and wide angle (up to 80 degrees) bending. Furthermore, the wearable and sensitive PDs have been applied to measure the heart rate in both red and near infrared (NIR) ranges. The presented PDs are expected to work as sensor candidates in integrated electronic skin. (C) 2014 AIP Publishing LLC.