Effect of electrodes and zeolite cover layer on hydrocarbon sensing with p-type perovskite SrTi0.8Fe0.2O3-δ thick and thin films

Selectivity enhancement of p-type semiconducting hydrocarbon sensors—The use of sol-precipitated nano-powders

“…For short saturated HC species such as methane or propane, where the sensitivity of thin films is reported to be low [10], the SP device performs best. Integration of PLD thin films and SP based thick films on a single sensor chip could thus lead to a very sensitive hydrocarbon sensor, which in addition has the potential to discriminate between saturated and unsaturated hydrocarbons.…”

“…According to former results [10], the use of platinum for electrical contacting is very advantageous. Hence, either a set of four platinum electrodes or two platinum interdigitated electrodes (IDE) were applied onto the substrate prior to Sr(Ti 1−x Fe x )O 3−δ film deposition.…”

“…In particular, the SrTi 1−x Fe x O 3−δ members with a moderate iron content (x = 0.1-0.2) show best performance [9,10].…”

Preparation, surface state and band structure studies of SrTi(1−x)Fe(x)O(3−δ) (x=0–1) perovskite-type nano structure by X-ray and ultraviolet photoelectron spectroscopy

“…The existence of oxygen vacancies in STF x is unavoidable because in this structure, when the iron atoms were replaced with the titanium atom and due to the difference in their preferential oxidation states (+4 for Ti and + 3 for Fe), oxygen vacancies were formed in order to maintain charge balance in the system [13,14]. STF x has found vast applications in oxygen sensor [14][15][16], hydrocarbon sensor [17], fuel cell [16,18], oxygen separation membranes [19] and phase shifters in communication systems [20], however the STF x compound is yet to be fully understood and more research is needed. This paper describes a simple procedure for the synthesis of STF x series (x = 0~1), with x at 0.2 interval, by a high temperature solid state reaction process (1200°C, two cycles in oxygen ambient with flow rate of 150 sccm).…”

Effect of a porous Pt/alumina cover layer for V₂O₅/WO₃/TiO₂ resistive SO₂ sensing materials

“…16) At the moment, the reason for the response increase towards propane is not clear, but a similar behavior occurs for platinum loaded zeolite covers on resistive hydrocarbon gas sensors. 17) One interpretation is as follows: A part of the propane molecules is partly oxidized on the Pt catalyst of the Pt/alumina layer, and then CO and hydrocarbon such as methanol, ethanol, and/or acetone are formed. Thus, the molecule number of CO and hydrocarbons increases more than that of propane.…”