title: Sensitive detection of hydrocarbon gases using electrochemically Pd-modified ZnO chemiresistors.
abstract: Pristine and electrochemically Pd-modified ZnO nanorods (ZnO NRs) were proposed as active sensing layers in chemiresistive gas sensors for hydrocarbon (HC) gas detection (e.g., CH4, C3H8,C4H10). The presence of Pd nanoparticles (NPs) on the surface of ZnO NRs, obtained after the thermal treatment at 550 °C, was revealed by morphological and surface chemical analyses, using scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The effect of the Pd catalyst on the performance of the ZnO-based gas sensor was evaluated by comparing the sensing results with those of pristine ZnO NRs, at an operating temperature of 300 °C and for various HC gas concentrations in the range of 30-1000 ppm. The Pd-modified ZnO NRs showed a higher selectivity and sensitivity compared to pristine ZnO NRs. The mean sensitivity of Pd-modified ZnO NRs towards the analyzed HCs gases increased with the length of the hydrocarbon chain of the target gas molecule. Finally, the evaluation of the selectivity revealed that the presence or the absence of metal nanoparticles on ZnO NRs improves the selectivity in the detection of specific HCs gaseous molecules.
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy; Department of Electrotechnics and Electronics, Politecnico di Bari, Bari, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Dilonardo
authors.affiliation: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Laboratory Functional Materials and Technologies for Sustainable Applications - Brindisi Research Center, Brindisi, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Penza
authors.affiliation: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Laboratory Functional Materials and Technologies for Sustainable Applications - Brindisi Research Center, Brindisi, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Alvisi
authors.affiliation: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Laboratory Functional Materials and Technologies for Sustainable Applications - Brindisi Research Center, Brindisi, Italy.
authors.forename: Gennaro
authors.initials: G
authors.lastname: Cassano
authors.affiliation: CNR-IFN Bari, Bari, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Di Franco
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Palmisano
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Torsi
authors.affiliation: Department of Chemistry, Università degli Studi di Bari Aldo Moro, Bari, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Cioffi
keywords: Pd-modified ZnO; ZnO nanorods; chemiresistive gas sensor; electrosynthesis; hydrocarbon gas sensor