Tuning CO2 sensitivity of HPTS by ZnO and ZnO@Ag nanoparticles

Improvement of the CO2 Sensitivity: HPTS-Based Sensors along with Zn@SnO2 and Sn@ZnO Additives

“…Techniques based on infrared absorptiometry, electrochemistry, and luminescence can be used to primarily identify the presence of CO 2 gas. Optical sensors have gained popularity in recent years as a result of their advantages, such as electrical isolation, minimal noise interference, lower cost, fast response, adaptability for miniaturization, and simplicity of production and use. − Currently, electrochemical and optical devices based on spectroscopic changes are used to measure CO 2 , but optical chemical measurement methods have advantages, such as shorter response times, greater sensitivity, stability, and lower prices. The most common pH-sensitive fluorescent indicator dye, 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS), is commonly used for the accurate and continuous monitoring of dissolved CO 2 gas in various research fields.…”

“…Despite the widespread use of HPTS dye in optical applications and its superior response to CO 2 , it exhibits some disadvantages, such as stability, low relative signal variation, and reproducibility. As such, HPTS dye has been used with various additives such as ionic liquids (ILs), metal oxide nanoparticles (NPs), , coordination polymers (CPs), and/or metal oxide semiconductors (MOSs) , to eliminate such disadvantages. By incorporating MOSs into the sensor design, it is possible to increase the sensitivity and selectivity toward gas molecules.…”

“…By incorporating MOSs into the sensor design, it is possible to increase the sensitivity and selectivity toward gas molecules. The porous structures of MOSs allow for a larger surface area available for gas adsorption, leading to enhanced sensing capabilities. , Metal oxide semiconductors (such as ZnO, CuO, SnO 2 , TiO 2 , Co 3 O 4 , Fe 2 O 3 , and WO 3 ), which have n-type and p-type forms, perform numerous gas sensing applications due to their chemical and physical properties and distinctive structure. ,− MOSs-based gas sensors detect many target gases, including both oxidizing and reducing gases such as O 2 , CO 2 , CO, NO 2 , H 2 , H 2 S, SO 2 , and CH 4 and solvent vapors such as ammonia, acetone, toluene, and ethanol. − Various metal oxide doping materials such as a MXene/CuO composite driven by TENG, a TENG-driven MXene/TiO 2 /SnSe composite, a Pd-doped CoTiO 3 /TiO 2 (Pd-CTT) nanocomposite, and a ZnO/SnSe 2 composite film for ammonia, SO 2 , benzene, and CO gas sensor applications were reported by Wang et al. − …”

Improvement of The CO2 Sensitivity of HPTS Along With ZnO/CuO Nanoparticles: A Comparative Study Between Core-Shell And Hybrid Structures

“…For this reason, it is very critical to measure CO2 values accurately, continuously, and precisely. The CO2 can be measured by infrared (IR) spectrometry (3), severinghaus glass electrode (4), and optical sensors (5)(6)(7). Recently, the usage of optical-based sensors for the quantitative determination of CO2 presents many advantages according to other detection methods and reduced noise interference, electrical isolation, remote sensing, and the possibility of miniaturization.…”

“…Among the used dyes in optical-based CO2 sensors, the most commonly used pH-sensitive fluorescent dye has been the trisodium salt of the 1-hydroxy-3, 6, 8 pyrenetrisulfonic acid (HPTS) or ion pair form of HPTS. HPTS has distinct emission and absorption bands in the visible light area (6). Fluorescent HPTS dye, which is pH sensitive, has previously been used in many carbon dioxide sensor studies (11)(12)(13)(14)(15).…”