Current-voltage characteristics of C70 solid near Meyer-Neldel temperature

Abstract

The current-voltage characteristics of the C70 solid with hexagonal closed-packed structures were measured in the temperature range of 250–450 K. The current-voltage characteristics can be described as a temporary expedient by a cubic polynomial of the voltage, i=av3+bv2+cv+d. Moreover, the Meyer-Neldel temperature of the C70 solid was confirmed to be 310 K, at which a linear relationship between the current and voltage was observed. Also, at temperatures below the Meyer-Neldel temperature, the current increases with increasing voltage. On the other hand, at temperatures above the Meyer-Neldel temperature a negative differential conductivity effect was observed at high voltage side. The negative differential conductivity was related to the electric field and temperature effects on the mobility of charge carrier, which involve two variations in the carrier concentration and the activation energy for carrier hopping transport.

Compensation Effect in Catalytic Oxidation of Carbon Monoxide

“…The first who found this phenomenon was Constable [8] for dehydrogenation of alcohol using different copper oxide cata-lysts, but it was rediscovered frequently in various fields receiving diverse names: the Barclay-Butler rule [9,10], the Meyer-Neldel effect [11][12][13], the theta rule [14], the Smith-Topley effect [15,16], or Zawadzki-Bretsznajder rule [17]. The compensation effect was found in a wide range of science from heterogeneous catalysis [18][19][20][21] to a variety of other areas of chemistry, namely, gas and liquid chemistry [22,23], coordination chemistry [24], antibiotics dissociation [25], hydrogen bonding [26], solid-phase thermal decomposition [27], degradation of polypropene composites [28], heat exchanger fouling studies [29], lignocellulosic biomass torrefaction [30], and much more [3].…”