Dynamic Studies on Mass (gravity) variation
The quartz crystal microbalance (QCM) is a variant of acoustic wave micro-sensors that are capable of ultrasensitive mass measurements. The mass sensitivity of the QCM originates from the dependence of the oscillation frequency on the total mass of the metal-coated crystal, given by the Sauerbrey equation. The EQCM adds a valuable tool in the analytical investigation of interfacial processes. QCM is coupled with electrochemistry experiment to build up in situ identification of Solid Electrolyte Interphase (also other interfacial process) called EQCM. In order to maintain moisture level during experiment, glove box, which combined with dry air machine, has been assembled. Bio logic machine is used to conduct electrochemistry experiment and connected with QCM module to perform sensitive mass change identification during electrochemical process.
Dynamic Studies on Laser Light signal variation
Surface plasma resonance (SPR) technique is an optical method for measuring the refractive index of very thin layers of material adsorbed on a gold metal, this measurement was well-established method for real-time, label-free monitoring of molecular interactions. Surface plasma resonance is a charge-density oscillation that may exist at the interface of two media with dielectric constants of opposite signs, for instance, a metal and a dielectric. The charge density wave is associated with an electromagnetic wave, the field vectors of which reach their maxima at the interface and decay evanescently into both media. The working principle of the SPR technique is based on utilizing visible light to excite free electrons on a surface of a metal, which in turn causes surface plasma to travel along the metal surface also creating an evanescent field to the adjacent medium in contact with the metal. This study develops new technique to identify SEI growth during electrochemical process at the same time. EC-SPR measurement performs using SPR Navi 200 combined with Bio logic machine. Linear sweep voltammetry is applied to study reduction potential of electrolyte and detected at the same time using SPR measurement.