A Study on Fiber Optic Temperature Sensor Using Al 2 O 3 as High Index Overlay for Solar Cell Applications

Recently, the performance of solar cell is impacted by rising panel temperatures. For solar cells to work at their best and have the longest possible useful life, the temperature of the panels must be kept at an ideal level. Current temperature sensors have a slow response time, poor accuracy, and low resolution. Meanwhile, Al2O3 and its derivatives have demonstrated a noteworthy role in temperature sensing applications due to its greater surface area, ease of synthesis, tailored optical characteristics, high melting point, and high thermal expansion coefficient. Al2O3-based nanoparticles have been employed in fiber optic-based temperature sensors as a sensing layer, a sensitivity improvement material, and a sensing matrix material. In this chapter, we discuss the function of Al2O3-based nanomaterials in evanescent wave-based temperature sensors, sensing characteristics such as sensitivity, linearity, and repeatability. The ZAZ-based sensor (Section 3.1) shows an operating temperature range between 100.9°C and 1111.0°C, the temperature sensitivity becomes 1.8 × 10-5/°C. The fabricated sensor had a linearity of 99.79%. The synthesized Al2O3 nanoparticles (Section 3.2) were given better linearity and high sensitivity (~27) at 697 nm compared with other sensing materials such as ZnO, SnO2, TiO2. The Al2O3-MgO (50-50%) (Section 3.3) demonstrated an ultrahigh sensitivity of 0.62%/°C with a better linear regression coefficient of 95%. The present advances and problems are also discussed in detail.