Development of High-Performance Bismuth Sulfide Nanobelts Humidity Sensor and Effect of Humid Environment on its Transport Properties

Abstract

Orthorhombic phase bismuth sulfide (Bi 2 S 3 ) nanobelts were prepared via liquid–solid phase reaction method. Bi 2 S 3 nanobelts were observed to be preferentially oriented along the (101) plane. Direct band gap (2.95 eV) and characteristic wavelength (λ max = 342 nm) were extracted through UV–visible spectroscopy. Specific surface area (9.8 m 2 /g) and pore size (2.5–120 nm) were evaluated through Brunauer–Emmett–Teller (BET) analysis. Relative humidity (RH) sensing properties were studied in the range of 11–97% RH at ambient conditions. The response of the sensor increases linearly with increase in RH. Fast response time (8–10 s) and recovery time (15 s) were observed. Reproducible and large response was also observed between 11 and 97% RH. Small hysteresis (<5%) and long-term stability during 30 days were confirmed. As a function of frequency, capacitance, alternating current conductivity, and electrical complex modulus in the frequency range of 20–2 MHz were studied at 11–97% RH. The sensing mechanism was also studied.

Bismuth-Based Gas Sensors: A Comprehensive Review

“…87,88 Bismuth Sulfide (Bi 2 S 3 )-Based Gas Sensors Only a few reports are available on Bi 2 S 3 -based gas and humidity sensors. 42,52 Kan et al measured NO 2 gas response of Pb(NO 3 ) 2 ,NaNO 2 , NaNO 3 , Zn(NO 3 ) 2 (as long-chain ligand exchanger)-treated Bi 2 S 3 films at room temperature. 42 They found that Pb(NO 3 ) 2 treatment generated more porous Bi 2 O 3 film that showed maximum response (58.8) as compared to other inorganic salt treatment.…”

“…42 Orthorhombic Bi 2 S 3 nanobelts were generated using a facile liquid-solid phase reaction technique by mixing a stoichiometric ratio of bismuth acetate (as a Bi source) and thiourea (as a sulphur). 52 Relatively low-temperature combustion (at 190°C) caused generation of very thin and porous nanobelts (pore size of 2.5-120 nm). The humidity sensor fabricated…”

“…from synthesized nanobelts exhibited a linear increase in relative humidity (RH). 52 They also established long-term stability (30 days) with fast response and recovery times of 8-10 s and 15 s, respectively. The typical humidity sensing response of a bismuth sulfide-based humidity sensor is given in Table I.…”

Preparation and application of one-dimensional nanomaterials derived from titanium carbide

“…近年来, 湿度传感器已 在呼吸速率检测、非接触式开关、皮肤湿度检测、婴 儿尿布润湿监测等方面获得实际应用. 目前, 石墨 烯 [98] 、硫化物 [99] 、金属氧化物 [100] 及其复合物 [101] 等材 料已被用作湿度传感器的活性材料. [45] .…”

One-Step Rapid Deposition of Bi2S3 Thin Film and Comprehensive Study of Its Photoelectrochemical Activity

“…Solar energy has been regarded as the most potential clean and environment-friendly energy source to tackle the increasingly serious energy shortage and environmental pollution. , Developing functional materials for achieving solar energy conversion has attracted much attention among researchers. In recent years, layered orthorhombic bismuth sulfide (Bi 2 S 3 ) has emerged as a kind of promising semiconductors candidate in photocatalysts, , photoelectrochemical (PEC) devices, , sensors, , photovoltaic devices, , thermoelectric devices, , electrochemical energy storage cells, , and photothermal therapy due to its excellent optical and electrical properties such as a relatively narrow band gap and a high absorption coefficient. − Moreover, the nontoxic nature of Bi 2 S 3 endows more competitiveness in green development compared with other metal chalcogenides . In the past decades, numerous reports have been focused on investigating the synthesis and properties of Bi 2 S 3 nanoparticles. ,− From the point of view of practical application, nanoparticles have several drawbacks, such as low reusability and strong light diffusion.…”