Photothermal-assist enhanced high-performance self-powered photodetector with bioinspired temperature-autoregulation by passive radiative balance

High broadband absorption with low angular dependence is one of the key factors for photoelectronic applications. Photo-heating accelerating carrier transfer, inducing a change in electrical conductance and exciting hot electrons promotes a photoelectric response and extends the response photon energies well below the semiconductor band edge. A photodetector requires cooling to prevent overheating and reduce thermal noise, thereby improving photoelectric detection. Here, these distinct, independent functions, especially the conflicting functions between photo-heating and cooling, are combined into the same structure for the first time. We present an innovative approach using a layered MoS2/nonlayered CdS/Au hybrid heterostructure integrated into a bioinspired sophisticated micro/nanoarchitecture with omnidirectional light-harvesting, effective photothermal conversion and temperature auto-regulation nature to design a self-powered room-temperature photodetector for low angle-dependence and photothermal-assisted broadband photoelectric detection without active cooling. In nearly active areas with a square micron scale, our photodetector attains a responsivity up to 132.06, 122.46 and 74.44 mA/W under an illumination of 660, 808 and 980 nm, respectively, operated under a low bias (0.5 V), which shows a significant advantage over the reported high-performance MoS2 heterostructure photodetectors. Our work shows the concept that photo-heating can be used to enhance photoelectric detection by passive radiative balance. Thus, this work offers a new way to design a novel broadband room-temperature optoelectronic detector that outperforms conventional photodetectors, enabling new technological capabilities.

Automated summary

High broadband absorption with low angular dependence is crucial for photoelectronic applications. This work presents an innovative approach integrating conflicting functions such as photo-heating and cooling into the same structure, to design a self-powered room-temperature photodetector with broadband photoelectric detection. The photodetector shows significant advantages over conventional MoS2 heterostructure photodetectors, achieving high responsivity under different illuminations without the need for active cooling.