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The article investigates the measurable parameters of thermoelectric power and cooling modules including hot and cold side temperatures, voltage, and current. Experiments were undertaken between the hot and cold sides of thermoelectric module and load resistance with various temperature differences. It states that information on the power output with varying temperature is essential when designing a thermoelectric power generation system.

Fluorine-doped tin dioxide (FTO) films were deposited on silicon wafers by inverted pyrosol technique using solutions with different doping concentration (F/Sn=0.00, 0.12, 0.75 and 2.50). The physical and electrical properties of the deposited films were analyzed by SEM, XRF, resistivity measurement by four-point-probe method and Hall coefficient measurement by van der Pauw method. The electrical properties showed that the FTO film deposited using the solution with F/Sn=0.75 gave a lowest resistivity of 3.2·10–4 ohm cm. The FTO films were analyzed by temperature programmed desorption (TPD). Evolved gases from the heated specimens were detected using a quadruple mass analyzer for mass fragments m/z, 1(H+), 2(H2 +), 12(C+), 14(N+), 15(CH3 +), 16(O+), 17(OH+ or NH3 +), 18(H2O+ or NH4 +), 19(F+), 20(HF+), 28(CO+ or N2 +), 32(O2 +), 37(NH4F+), 44(CO2 +), 120(Sn+), 136(SnO+) and 152(SnO2 +). The majority of evolved gases from all FTO films were water vapor, carbon monoxide and carbon dioxide. Fluorine ( m/z 19) was detected only in doped films and its intensity was very strong for highly-doped films at temperature above 400°C. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) is a useful material for gas-sensing applications because of its high surface to volume ratio structure. In this work, multi-wall CNTs are incorporated into tin oxide thin film by means of powder mixing and electron beam evaporation and the enhancement of gas-sensing properties is presented. The CNTs were combined with SnO2powder with varying concentration in the range of 0.25–5% by weight and electron beam evaporated onto glass substrates. From AFM and TEM characterization, CNT inclusion in SnO2thin film results in the production of circular cone protrusions of CNT clusters or single tube coated with SnO2layer. Experimental results indicate that the sensitivity to ethanol of SnO2thin film increases by the factors of 3 to 7, and the response time and recovery time were reduced by the factors of 2 or more with CNT inclusion. However, if the CNT concentration is too high, the sensitivity is decreased. Moreover, the CNT doped film can operate with good sensitivity and stability at a relatively low temperature of 250–300∘C. The improved gas-sensing properties should be attributed to the increasing of surface adsorption area of metal oxide produced by CNT protrusion. [ABSTRACT FROM AUTHOR]