Synthesis and morphological control of self-powered broadband photodetector material: A study of bottle brush Co3O4/ZnO heterojunction

Self-powered broadband photodetectors operating in the ultraviolet-visible-near infrared (UV-Vis-NIR) range are pivotal for various applications, including optical communication, military surveillance, multispectral sensing, and environmental monitoring. In this study, we present an innovative approach to fabricate a bottlebrush nanostructure employing the Co3O4/ZnO PN junction. This unique design allows the photodetector to function efficiently without bias condi-tions, providing a versatile platform for a wide range of detection capabilities. The morphology of the photodetector is precisely controlled by manipulating the concentration of the growth solution containing cobalt tetroxide. Specifically, maintaining a concentration of 10 mM results in a welldefined bottlebrush heterojunction that exhibits highly efficient detection performance in the UV-Vis-NIR region. The maximum achievable responsivity (R) and specific detectivity. (D) are noteworthy, reaching values of 103.3 mA W-1 and 1.58 x 1014 Jones, respectively. These findings present a novel strategy for developing broadband photodetectors based on stable, nontoxic, and cost-effective metal oxides, opening new possibilities for advancements in photodetection technology.