Laboratory in Materials Science and Physical Engineering
Paper by H. Okcu 2025
The paper "Fabrication of visualized NO gas sensing system operable at near room temperature" has been published in J. Power Sources
to
Here you-ll find Hayri's paper
" A chemiresistive gas sensor capable of sensing NO gas at near-room temperature (50 °C) is fabricated by depositing ZnO film using the dry-deposition method, Nano-Particle Deposition System (NPDS). We aim to overcome the limitations of conventional NO gas sensors that require high operating temperature of approximately 300 °C. A gas-sensing visualization system is developed to provide instant information of target gas. The gas sensor with viologen-based electrochromic device, is connected via Arduino to demonstrate a sensing system. The ZnO gas sensor exhibits high surface roughness of 0.583 μm. Due to oxygen vacancies on the surface, the sensor demonstrates a response of 14 % to 200-ppm NO gas under low temperature of 50 °C. The viologen-based electrochromic device displays various colors depending on the applied voltage, while maintaining stability over 100 cycles. Using this gas-sensing visualization system, the electrochromic device changes to a yellow state upon exposure to 200-ppm NO gas at 50 °C and switches to a green state when exposed to air. Cycling tests confirm that this response is maintained for 40 cycles. This demonstrates the feasibility of the proposed gas-sensing visualization system operable near room temperature, offering potential alternative to chemiresistive sensors that are more reactive at high temperatures."