Preparation of BiOI-Functionalized ZnO Nanorods for Ppb-Level NO₂ Detection at Room Temperature

Abstract

Light activation is an effective method to improve sensor performance at room temperature (RT). This work realized the effective detection of trace-level NO 2 at RT under visible light by combining ZnO with the excellent photocatalyst BiOI. A 1.5 atom % BiOI−ZnO-based sensor under 520 nm light exhibited optimal sensing properties with the maximum responses (13.9 to 1 ppm NO 2 ), fast response/recovery time (66 s/47 s to 1 ppm), and a low detection limit of 25 ppb (theoretically 0.34 ppb). In the meantime, the sensor also possessed excellent selectivity, repeatability, and stability. The excellent properties were attributed to the high concentration of oxygen vacancies and the prolonged lifetime of photogenerated carriers. In addition, the observed photovoltaic effect of the sensor at RT indicated that the sensor held application prospects in the photovoltaic self-power field.

Potential application of bismuth oxyiodide (BiOI) when it meets light

“…8 (a) Schematic fabrication process, (b) response curves under 520 nm light, and (c) working mechanism of BiOI-based NO 2 sensors. 126 Adapted with permission from American Chemical Society copyright 2022.…”

“…In recent years, there has been increasing interest in the development of BiOI-based light-assisted sensors for various applications. 110–130 The reported BiOI-based sensors mainly include PEC-type sensors and solid-state sensors in different fields such as environmental monitoring, biomedical research, diagnosis of diseases, analysis of biological molecules, gas detection, and chemical analysis. Fig.…”

“…8). In this report, 126 BiOI was used as the photosensitizer. The decoration of ZnO with BiOI effectively enhanced the selectivity and repeatability under visible light illumination because of the increasing number of oxygen vacancies as shown in Fig.…”

Adsorption of NO2, NO, NH3, and CO on Noble Metal (Rh, Pd, Ag, Ir, Pt, Au)-Modified Hexagonal Boron Nitride Monolayers: A First-Principles Study

“…1−3 Moreover, recent investigations have shown that NO 2 is closely related to the prevention and transmission of COVID-19. 4,5 And it is also a significant account of environmental pollution such as summer smog, acid rain, and PM 2.5, which poses a major endangerment to mankind's health and the safety of other life on the earth. 6,7 According to the OSHA regulations, the maximum concentration of short-term exposure to NO 2 is 5 ppm in industry.…”

“…As a common gas in industrial production, nitrogen dioxide (NO 2 ) can lead to grave respiratory problems, including inflammation of the trachea and accumulation of fluid in the lungs. − Moreover, recent investigations have shown that NO 2 is closely related to the prevention and transmission of COVID-19. , And it is also a significant account of environmental pollution such as summer smog, acid rain, and PM 2.5, which poses a major endangerment to mankind’s health and the safety of other life on the earth. , According to the OSHA regulations, the maximum concentration of short-term exposure to NO 2 is 5 ppm in industry. Long-term exposure to high concentrations of NO 2 can lead to poor breathing, lung disease, and even death. , Additionally, nitric oxide (NO) is a major contributor to air pollution and can have an unfavorable influence on mankind’s health.…”