The electrocatalytic effect exerted by hematite, a ubiquitous component of clay bodies, on the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) can be used to acquire information on archaeological ceramics. The solid-state voltammetric response of different hematite and ochre specimens, accompanied by SECM analysis in contact with 0.10 M HCl aqueous solution, is described. In air-saturated solutions, catalytic effects on the ORR and OER are accompanied by Fe(III)/Fe(II) and Fe(IV)/Fe(III) redox reactions. Such processes are conditioned by a variety of factors, the hydroxylation degree of the mineral surfaces being particularly influential, and exhibit significant variations upon heating the specimens between 300 and 900 °C. Voltammetric measurements carried out on a set of archaeological samples of Apulian red-figured pottery dated back within 5th and 4th centuries BCE permit to obtain site-characteristic voltammetric profiles.
Hematite as an Electrocatalytic Marker for the Study of Archaeological Ceramic Clay bodies: A VIMP and SECM Study**
Giannuzzi M.;Mangone A.;Giannossa L. C.;
2022-01-01
Abstract
The electrocatalytic effect exerted by hematite, a ubiquitous component of clay bodies, on the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) can be used to acquire information on archaeological ceramics. The solid-state voltammetric response of different hematite and ochre specimens, accompanied by SECM analysis in contact with 0.10 M HCl aqueous solution, is described. In air-saturated solutions, catalytic effects on the ORR and OER are accompanied by Fe(III)/Fe(II) and Fe(IV)/Fe(III) redox reactions. Such processes are conditioned by a variety of factors, the hydroxylation degree of the mineral surfaces being particularly influential, and exhibit significant variations upon heating the specimens between 300 and 900 °C. Voltammetric measurements carried out on a set of archaeological samples of Apulian red-figured pottery dated back within 5th and 4th centuries BCE permit to obtain site-characteristic voltammetric profiles.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
