Electrical conduction in copper phosphate glasses containing nickel or cobalt

Abstract

A variation in d.c. conductivity and activation energy of 35 mol % CUO-65 mol % PzO~ glasses is observed as CuO is gradually replaced by NiO or CoO. These results are believed to be due to the change in the redox ratio of the two transition metal oxide glasses, which causes an increase and then a decrease of polaron hopping transitions between the ions of the same element and between the ions of the different transition metal elements.

Mixed ion–polaron transport in Na2O–PbO–Fe2O3–P2O5 glasses

“…The values for s calculated at 303 and 363 K, Table 4, lie in the range 0.60 6 s 6 0.83 for glasses of Na 2 O content 615 mol%. This confirms polaron hopping between Fe(II) to Fe(III) ions [28]. For glasses of higher Na 2 O content, >15 mol%, the values for s are smaller, in the range 0.36 6 s 6 0.61, suggesting the domination of ionic conduction.…”

Dielectric study and ac conductivity of iron sodium silicate glasses

“…3. The values of the constant s calculated for the investigated samples and shown in Table 3, lie in the range 0.8 b s b 1 in the case of undoped glass sample and that of low iron content, which confirm the expectation of the polaron hopping between Fe 2+ and Fe 3+ ions [23]. Also the values of the parameter A are reported in Table 3.…”

Influence of lithium phosphate concentration and temperature on the electrical conduction of (76V2O5–24P2O5)1−X (Li3PO4)X glasses

“…In addition, it shows a transition region at which the conduction process may change. The two regions intersect at definite temperature ðT ¼ T x Þ which can be obtained by using the equation 4 . This shows that, Debye temperature is shifted towards the lower temperature range [10].…”

“…Semiconducting glasses [1,2] have attracted a great attention because of their intriguing electrical properties and technological applications. The electrical conduction in oxide glasses containing transition metal ions (TMI) has two different oxidation states takes place by means of small polaron hopping [3,4]. Many authors have studied the effect of additives on electrical properties of vanadium phosphate glasses [5 -8].…”