INFICON RQCM - Quartz Crystal Microbalance Research System - Manual (Page 57)

RQCM – RESEARCH QUARTZ CRYSTAL MICROBALANCE
THEORY OF OPERATION 5-5
Palladium Pd 12.00 24.73
Platinum Pt 21.40 36.04
Potassium Chloride KC 1.98 4.31
Rhenium Re 21.04 58.87
Rhodium Rh 12.41 42.05
Samarium Sm 7.54 9.92
Scandium Sc 3.0 9.70
Selenium Se 4.82 10.22
Silicon Si 2.32 12.40
Silicon (II) Oxide SiO 2.13 10.15
Silicon Dioxide (fused quartz) SiO
2
2.2 8.25
Silver Ag 10.50 16.69
Silver Bromide AgBr 6.47 7.48
Silver Chloride AgCl 5.56 6.69
Sodium Na 0.97 1.84
Sodium Chloride NaCl 2.17 5.62
Strontium Sr 2.620 ----
Sulphur S 2.07 3.86
Tantalum Ta 16.60 33.70
Tantalum (IV) Oxide Ta
2
O
5
8.2 29.43
Tellurium Te 6.25 9.81
Terbium Tb 8.27 13.38
Thallium Tl 11.85 5.70
Tin Sn 7.30 12.20
Titanium Ti 4.50 14.06
Titanium (IV) Oxide TiO
2
4.26 22.07
Tungsten W 19.30 54.17
Tungsten Carbide WC 15.60 58.48
Uranium U 18.70 37.10
Vanadium V 5.96 16.66
Ytterbium Yb 6.98 7.81
Yttrium Y 4.34 10.57
Zinc Zn 7.04 17.18
Zinc Oxide ZnO 5.61 15.88
Zinc Selenide ZnS 5.26 12.23
Zinc Sulfide ZnS 4.09 11.39
Zirconium Zr 6.51 14.72
5.4 LIQUID MEASUREMENTS
QCMs have been used as gas-phase mass detectors with lossless films for many years. However,
only recently has their applications been extended to liquids and with viscoelastic deposits. In
these cases, both frequency and series resonance resistance ∗ of the quartz crystal are important to
completely characterize the material and/or the liquid in contact with the crystal electrode. The
development of QCM systems for use in liquids opened a new world of applications, including
electrochemistry and micro-rheology. More recent developments have focused on tailoring
electrode surface chemistry (i.e. specialized polymer coatings) so that these devices can be
applied as discriminating mass detectors for many applications including: specific gas detection,
environmental monitoring, biosensing and basic surface-molecule interaction studies.
∗ See Section 5.6 for a detail discussion.