Electrical properties of thin-films of the mixed ionic-electronic conductor CuBr: influence of electrode metals and gaseous ammonia

Sensing of carbon monoxide gas in reducing environments

“…There are two metal halides that have been previously reported for sensing studies, AgCl [18,19] and CuBr [13][14][15][16][17]20]. The species that have been examined are NH 3 and (CN) 2 , and both these molecules form coordination complexes with the metal ion.…”

“…Adsorption of NH 3 on AgCl was proposed to lead to increase in interfacial resistances. Lauque et al considered the interfacial resistance mechanism to explain the increase in resistance upon interaction of CuBr with NH 3 [17]. In addition, they also considered that increase of electron concentration in the space charge region upon Cu þ migration to the surface leads to an increase in electron concentration and thereby, a decrease in the majority carriers, which are holes.…”

“…Current-voltage curves show non-linear response for cells of the type Au/CuBr/Au and was explained as arising from blocking of the ionic current [17]. For Cu/CuX/ graphite cells, current was proposed to be exclusively carried by holes [22].…”

“…Knauth and co-workers, in a series of papers have studied the conduction properties of CuBr under ambient conditions and also demonstrated that sputtered films of CuBr can be used for NH 3 sensing via resistance measurements [13][14][15][16][17]. They have interpreted the current-voltage characteristics of the CuBr films with p-type semiconductivity of the films and a reduced copper deficiency on copper substrates.…”

Numerical models for ionic conduction in CuBr-TiO2 composites and for electrolysis of CuBr films

“…The simplest case of two different grain sizes of ionic conductor is studied. Thin films of CuBr can be used as a dc conductometric gas sensor for ammonia [11,12]. This is probably also related to space charge effects, because mobile copper ions can be trapped at the thin-film surface by the ammonia molecules, which are known to form very stable complexes with copper ions in aqueous solutions.…”