Development of a high-sensitivity plasticizer sensor based on a quartz crystal microbalance modified with a nanostructured nickel hydroxide film

Abstract

Nanostructured nickel hydroxide (nano-Ni(OH) 2 ) was synthesized at a low temperature without annealing. Accordingly, a plasticizer sensor based on a quartz crystal microbalance (QCM) modified with the nano-Ni(OH) 2 sensing film was fabricated to detect dibutyl phthalate (DBP) and its relative film thickness was optimized. The sensor worked at room temperature and exhibited a high sensitivity of 4.91 Hz ppb −1 to DBP in a low concentration range of 5-20 ppb, and an ultra-low detection limit of 5 ppb was achieved. In addition, the sensor maintained good repeatability as well as stability shown by the experimental data. The responses to five possible interferences and four other plasticizers were also measured, which indicated the excellent selectivity of the sensor and its potential use in monitoring plasticizers in a gaseous state.

A Noncontact Dibutyl Phthalate Sensor Based on a Wireless-Electrodeless QCM-D Modified with Nano-Structured Nickel Hydroxide

“…Then, with the concentration increased, the increments of the mass adsorbed become fewer. The sensitivity was achieved as 2.4 Hz/ppb, which is the same as the previous work [ 14 ], showing that the wireless method of data acquisition would not affect the adsorption process itself. Finally, the limit of detection of the sensor was achieved as 1.2 ppb (calculated as three times the signal-to-noise ratio).…”

“…With the noncontact configuration, wires or electrodes were removed so that damage to the chamber for wire was avoided and the operated frequency was raised to 3rd harmonics. Nano-structured nickel hydroxide [ 14 ] was used as the sensing film. With the 3rd harmonics operating frequency (18 MHz), a higher sensitivity of 7.3 Hz/ppb was achieved with half the usage of the sensing material.…”

“…The preparation of nano-Ni(OH) 2 was carried out in the same way as the previous work [ 14 ]. Before the experiment, the quartz plates should be coated with nano-Ni(OH) 2 as the sensing film.…”

“…Wang [ 12 ] deposited the polyaniline nanofibers on the electrode of a quartz crystal oscillator as the sensitive film and detected the DBP in the range of 20–1000 ppb with a detection limit of 20 ppb. Hu and Zhang [ 13 , 14 ] respectively used nano-structured nickel hydroxide and Au-decorated ZnO to coat QCM sensors and achieved a detection range of 5–40 ppb and 2–30 ppb with detection limits of 5 ppb and 2 ppb.…”

“…This system could simultaneously monitor the frequency and the dissipation value in a noncontact way, which means that it combines both the advantages of the quartz crystal microbalance with dissipation (QCM-D) system [ 17 ] and the wireless-electrodeless QCM system [ 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. Based on this system, a DBP sensor was constructed and nano-structured nickel hydroxide [ 14 ] was deposited as the sensing film. The depositing load of the sensing film was optimized and the sensor performance including sensitivity, selectivity and limit of detection was evaluated.…”