Modulate Transparent Optoelectronic Device Performances of Self‐Power and High‐Speed Using Transparent Conducting Substrates

ABSTRACT (Optoelectronic devices are essential for various applications, and their transparent photovoltaic versions offer greater flexibility for self‐powered optoelectronics in sensing, system miniaturization, and data‐driven learning. This study explores the use of transparent conducting substrates (TCS) to modulate optoelectronic performances through effective carrier concentration, which determines whether heterojunctions are more suitable for photovoltaics or self‐powered photosensing applications. The TCS includes doped semiconductors, metal nanowire networks, and oxide/metal/oxide multilayered materials to form transparent heterojunctions, which are carefully designed. The structural, optical, and electrical properties of TCS are investigated to understand their role in designing application‐suitable transparent heterojunction devices (THD). TCS plays a crucial role in tuning device electrostatics, enabling improved photovoltaic performance (open circuit voltage of 422 mV, short circuit current density of 2.2 mA cm −2 , fill factor of 48% and power conversion efficiency of 4.39% under 365 nm) with onsite power and photosensing capabilities with fast response times (54 µs). Among the TCS, highly doped metal oxides are particularly significant due to the role of dopants in junction formation, as revealed from impedance spectroscopy. Additionally, metal substrates, including nanowire networks and ultrathin‐metal‐oxide composites demonstrate self‐powered photoresponses through the pyro‐phototronic effect, offering stable and enhanced performance. This study demonstrates versatile deployment of oxide heterostructure on a variety of substrates for developing data‐driven applications of photocommunication and self‐powered sensors, while highly doped oxide can be preferred for onsite power generation applications for sustainable optoelectronics.)