Recent advances of photoacoustic spectroscopy techniques for gases sensing

Photoacoustic spectroscopy has been an important branch of spectroscopy, which refers to a kind of spectral sensing technology that converts sample absorbed optical energy into acoustic detection wave through photoacoustic effect and realizes detection of sample composition and concentration analysis with acoustic sensor. In addition to high selectivity and high sensitivity of the spectrum absorption, photoacoustic spectroscopy offers several intrinsic attractive features, including signal only related to sample light absorption, free from scattered light, zero background and signal proportional to optical power, as well as measured with wavelength-independent acoustic transducers. More and more applications have been found in the fields of environmental monitoring, industrial process control and detection, medical diagnosis and hazardous chemicals detection in national defense. Besides the traditional resonant photoacoustic spectroscopy technology, there have been new techniques such as cantilever enhanced photoacoustic spectroscopy, quartz tuning fork enhanced photoacoustic spectroscopy and multi-channel photoacoustic spectroscopy. The recent advances of photoacoustic spectroscopy techniques for gases sensing are reviewed, and their application prospects and future development trends are analyzed.