This study investigates the fabrication of a vertically aligned TiO

$_{\text{2}}$

/SnO

$_{\text{2}}$

heterojunction nanowire (NW) using e-beam evaporation with glancing angle deposition (GLAD). The sensing properties of the fabricated device were tested with different ppm of ethanol and acetone. The device demonstrated a significant response (

$\textit{S}$

) of

$\sim$

3.2 at concentrations of 200 ppm of ethanol at 150

$^{\circ}$

C with the corresponding response and recovery times of

$\sim$

41 and

$\sim$

84 s, respectively, at

$+$

3-V bias. The recorded values of current at

$+$

3 V are

$\sim$

0.1 and

$\sim$

0.8 mA for ambient conditions and ethanol (under 200 ppm), respectively. It is interesting to observe the sensing performance of the metal–oxide–semiconductor (MOS) heterojunction NW-based gas sensor, which can be attributed to the synergistic effect and large surface-to-volume ratio of vertically aligned TiO

$_{\text{2}}$

/SnO

$_{\text{2}}$

heterostructure NWs that enhances the absorption and desorption processes. This study marks the first time report on a GLAD-based SnO

$_{\text{2}}$

-NW/TiO

$_{\text{2}}$

-NW heterostructure gas sensor, showcasing its potential for practical applications in environmental monitoring and gas sensing technologies.

Sapam Bikesh

Publications