Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Sulfur-Doped Graphene-Supported Nickel-Core Palladium-Shell Nanoparticles as Efficient Oxygen Reduction and Methanol Oxidation Electrocatalyst
Δημιουργός/Συγγραφέας:	Perivoliotis D.K. Sato Y. Suenaga K. [EL] Ταγματάρχης, Νίκος[EN] Tagmatarchis, Nikos
Εκδότης:	American Chemical Society
Ημερομηνία:	2018
Γλώσσα:	Αγγλικά
ISSN:	2574-0962
DOI:	10.1021/acsaem.8b00631
Περίληψη:	The design of novel platinum-free highly efficient electrocatalysts for the oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) has been regarded as the core challenge toward the development of commercially available fuel cell devices. In this contribution, a facile strategy was applied to prepare surfactant-free nickel-core palladium-shell nanoparticles, abbreviated as Pd@NiNPs, uniformly distributed on sulfur-doped graphene (SG). The Pd@NiNPs/SG hybrid material was realized by employing a modified polyol method for the in situ preparation of NiNPs/SG, followed by deposition of a Pd shell through the galvanic replacement method and complementary characterization by Raman and IR spectroscopy, STEM/EELS, SEM, and EDS as well as XRD and TGA. The Pd-to-Ni molar ratio was optimized in view of the hybrid's electrocatalytic performance. Interestingly, the Pd@NiNPs/SG hybrid was proved to be a highly efficient and stable electrocatalyst toward ORR and MOR. It exhibited comparable initial ORR performance with the benchmark Pd/C catalyst and importantly greater stability, as after 2,000 potential cycles it possesses 36% and 67% higher diffusion-limited and kinetic current density, respectively, having a minimal loss of its initial activity. Further investigations on the reaction kinetics showed a four-electron direct reduction of oxygen to water for the Pd@NiNPs/SG as well as Tafel slopes of -48 mV dec-1/-116 mV dec-1, values much closer to those proposed for the polycrystalline platinum. In addition, Pd@NiNPs/SG revealed enhanced MOR specific activity by 82% over Pd/C (2.26 mA cm-2 vs 1.24 mA cm-2) and by far better antipoisoning abilities. Overall, Pd@NiNPs/SG hybrid is a highly efficient and low-cost electrocatalyst, revealing huge potential for application in high-performance energy conversion devices.
Τίτλος πηγής δημοσίευσης:	ACS Applied Energy Materials
Τόμος/Κεφάλαιο:	1
Τεύχος:	8
Σελίδες:	3869-3880
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry [EL] Φασματοσκοπία[EN] Spectroscopy
Λέξεις-Κλειδιά:	core-shell nanoparticles hybrid electrocatalysts methanol oxidation reaction oxygen reduction reaction sulfur-doped graphene
Αξιολόγηση από ομότιμους (peer reviewed):	Ναι
Κάτοχος πνευματικών δικαιωμάτων:	© 2018 American Chemical Society.
Σημειώσεις:	European Commission, EC; Japan Society for the Promotion of Science, JSPS: 16K05948, JP16H06333; General Secretariat for Research and Technology, GSRT; European Regional Development Fund, FEDER; Hellenic Foundation for Research and Innovation, HFRI: MIS 5002409 Financial support through a Ph.D. scholarship by the General Secretariat for Research and Technology (GSRT)−Hellenic Foundation for Research and Innovation (HFRI) to D.K.P. (Grant 95) is acknowledged. N.T. acknowledges support of this work by the project “Advanced Materials and Devices” (MIS 5002409) which is implemented under the “Action for the Strategic Development on the Research and Technological Sector”, funded by the Operational Programme “Competitiveness, Entrepreneurship and Innovation” (NSRF 2014-2020) and co-financed by Greece and the European Union (European Regional Development Fund).
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο