Learn More
Quartz-enhanced photoacoustic spectroscopy (QEPAS) with a single-tube acoustic microresonator (AmR) inserted between the prongs of a custom quartz tuning fork (QTF) was developed, investigated, and optimized experimentally. Due to the high acoustic coupling efficiency between the AmR and the QTF, the single-tube on-beam QEPAS spectrophone configuration(More)
Quartz-enhanced photoacoustic spectroscopy (QEPAS) based on double acoustic microresonators (AmRs) is developed and experimentally investigated. The double AmR spectrophone configuration exhibits a strong acoustic coupling between the AmR and the quartz tuning fork, which results in a ∼5  ms fast response time. Moreover, the double AmRs provide two(More)
We prepared the exfoliation of graphite, which was necessary for the production of graphene sheets that are desirable for the fabrication of nano-composites. Then a Solution-Processable Functionalized Graphene (SPFGraphene) with functionalization groups doped with P3HT hybrid thin film-based organic photovoltaic cells (OPVCs) was systematically identified(More)
Chemical vapor deposition (CVD) method is considered to be an efficient way to prepare Van der Waals heterostructure. However, accurately and hurtlessly identifying the layers number of MoS(2) in the heterostructure is still a challenge. Here, we calculated the expected contrast between MoS(2)/graphene heterostructure and underlying SiO(2)/Si substrate by(More)
A near-IR CO trace gas sensor based on quartz-enhanced photoacoustic spectroscopy (QEPAS) is evaluated using humidified nitrogen samples. Relaxation processes in the CO-N2-H2O system are investigated. A simple kinetic model is used to predict the sensor performance at different gas pressures. The results show that CO has a ~3 and ~5 times slower relaxation(More)
A selective and sensitive quartz enhanced photoacoustic spectroscopy (QEPAS) sensor, employing an erbium-doped fiber amplifier (EDFA), and a distributed feedback (DFB) laser operating at 1582 nm was demonstrated for simultaneous detection of ammonia (NH₃) and hydrogen sulfide (H₂S). Two interference-free absorption lines located at 6322.45 cm(-1) and(More)
A sub-ppb-level nitrogen dioxide (NO<sub>2</sub>) QEPAS sensor is developed by use of a cost-effective wide stripe laser diode (LD) emitting at 450 nm and a novel background noise suppression method called scattered light modulation cancellation method (SL-MOCAM). The SL-MOCAM is a variant of modulation spectroscopy using two light sources: excitation and(More)
Hydrophobic graphene-based material at the nanoscale was prepared by treatment of exfoliated graphene oxide with organic isocyanates. The lipophilic modified graphene oxide (LMGO) can then be exfoliated into the functionalized graphene nanoplatelets that can form a stable dispersion in polar aprotic solvents. AFM image shows the thickness of LMGO is(More)
In this paper, a simple, rapid and highly sensitive method for detecting trace amount of clenbuterol based on gold nanoparticles (GNPs) encapsulated with melamine was investigated. Morphological characterization using SEM and AFM revealed that the size of obtained GNPs was about 15 nm. The hydrogen-bonding interaction existed between clenbuterol and(More)
A Quartz-enhanced photoacoustic sensor using a custom quartz tuning fork with large prong spacing was realized and optimized by improving its spectrophone design and performance. The impact of two-tube and single-tube on-beam micro-resonator (mR) geometries on the detected signal and signal-to-noise ratio (SNR) was investigated. Experimental studies(More)