Large near-infrared lateral photovoltaic effect in an organic egg albumin/Si structure

Abstract

Previously reported photoelectric devices have mainly been limited to inorganic materials. Even though preparing high-performance photoelectric devices with organic biomaterials is an inevitable trend in commercialization, fabricating organic photoelectric devices based on naturally occurring materials with high sensitivity remains a great challenge due to the high resistivity of and few free electrons in these materials. Herein, high-performance photoelectric devices based on an egg albumin (EA)/Si structure are proposed, and a new, to the best of our knowledge, perspective is provided on photodetection in naturally occurring materials by utilizing the surface state of p-Si to separate light-induced carriers effectively. The free electrons of metal atoms restrain the surface states, leading to a sensitivity of 5 mV/mm for metal/Si devices, while the sensitivity of the EA/Si device in the near-infrared region is greatly promoted to 357 mW/mm, which is intimately related to the lack of effect of EA on the dangling bonds of the surface. The EA/Si device is among the most sensitive organic near-infrared photoelectronic device to date. This work opens up new avenues to overcome the obstacle of the low sensitivity of organic photodetectors, indicating that the EA/Si device has great potential for future applications in flexible photovoltaic devices.