title: A cross-functional nanostructured platform based on carbon nanotube-Si hybrid junctions: where photon harvesting meets gas sensing.
abstract: A combination of the functionalities of carbon nanotube (CNT)-Si hybrid heterojunctions is presented as a novel method to steer the efficiency of the photovoltaic (PV) cell based on these junctions, and to increase the selectivity and sensitivity of the chemiresistor gas sensor operated with the p-doped CNT layer. The electrical characteristics of the junctions have been tracked by exposing the devices to oxidizing (NO2) and reducing (NH3) molecules. It is shown that when used as PV cells, the cell efficiency can be reversibly steered by gas adsorption, providing a tool to selectively dope the p-type layer through molecular adsorption. Tracking of the current-voltage curve upon gas exposure also allowed to use these cells as gas sensors with an enhanced sensitivity as compared to that provided by a readout of the electrical signal from the CNT layer alone. In turn, the chemiresistive response was improved, both in terms of selectivity and sensitivity, by operating the system under illumination, as the photo-induced charges at the junction increase the p-doping of CNTs making them more sensitive to NH3and less to NO2.
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.|CNR-INO and Sensor Lab, Dept. of Information Engineering, University of Brescia, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Rigoni
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Pintossi
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Drera
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Pagliara
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Lanti
authors.affiliation: Dipartimento di Fisica, Università di Roma, Tor Vergata, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Castrucci
authors.affiliation: Dipartimento di Fisica, Università di Roma, Tor Vergata, Italy.
authors.forename: M
authors.initials: M
authors.lastname: De Crescenzi
authors.affiliation: Surface Science and Spectroscopy Lab @ I-Lamp and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Sangaletti