Synergistic Performance of Vertically Aligned SnO₂-NW/TiO₂-NW Heterojunction for Ethanol Sensing and Photodetector Application

This study reports on the performance of vertically aligned nanowire (NW) heterostructure based on SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>2</roman></sub>-NW/TiO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>2</roman></sub>-NW, highlighting its enhanced capabilities in both ethanol sensing and photodetection. The glancing angle deposition (GLAD) technique is employed to fabricate the NW-heterostructure. The device exhibits a high response to ethanol, with a Ra/Rg value of 2.02 at 50 ppm under 150 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∘</sup>C. The response and recovery times are ~68 and ~41 s, respectively. The device achieves a responsivity of 1.13 A/W and detectivity of 6.87 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>11</roman></sup> Jones at 405 nm and demonstrates robust photodetection performance with a rise time and fall time of ~0.13 s and ~0.11 s, respectively. The synergistic combination of SnO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>2</roman></sub>-NW and TiO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><roman>2</roman></sub>-NW, interface phenomenon, and polycrystalline nature offers enhanced gas sensing and photodetection performance. This study highlights the promising potential of dual-functional sensing technologies fabricated using the GLAD technique.