Pyro-Phototronic Effect in n-Si/p-MoO_3−x Heterojunction: an Approach to Improve the Photoresponse of the Ultraviolet Photodetector

The pyro-phototronic effect plays a crucial role in UV photodetection to enhance the overall device performance. Herein, the pyro-phototronic effect is demonstrated for the first time in n-Si/MoO_3−x heterostructures. Vertically grown 2D-MoO_3−x microstructures are synthesized that show a centrosymmetric structure. Commonly, non-centrosymmetric structures show a pyroelectric polarization effect; however, in the present work, authors have shown such a synergetic effect in a centrosymmetric MoO_3−x-based heterojunction. The fabricated device depicts a type I heterojunction that helps to reduce the response time and consequently minimizes charge-carrier recombination losses. UV photodetection is measured with very low power, and significant device performances are observed under varying light intensities. The maximum responsivity and detectivity are attained up to 4.4 mA W⁻¹ and 5.5 (Formula presented.) 10¹⁰ Jones under photoelectric effects. Additionally, the maximum responsivity and detectivity are attained up to 7.82 mA W⁻¹ and 10¹¹ Jones under the pyro-phototronic effect. Herein, an in-depth understanding of the pyro-phototronic effect in working phenomenon in type I heterojunction is provided. Such a mechanism can be explored in different heterojunctions to enhance photodetection performance in ultrafast light communications.