We are trying to introduce the exciton model to explain the infrared response of our devices based on CNPs [
17-
19]. In our experiment, the amount of excitons generated in CNPs increased with the infrared power density they received, contributing to a large photocurrent since the excitons are dissociated to electron-hole pairs by electrical field or/and thermal [
18], which was shown in Fig. 2(a). In addition, the thermal insulated PDMS substrate [
6] could inhibit fast thermal dissipation without exciton excitation and preserved more thermal energy to produce excitons in CNPs, thus increase the photocurrent response of the fabricated infrared sensors. In a word, the optoelectronic characteristics of CNPs and the thermal insulating substrate benefit for the superior photoresponse of the fabricated infrared sensor.