We report on the preparation of hydroxyapatite (HA) nanoparticles with high specific surface area, terminated with calcium-rich {0 1 0} facets, and their subsequent surface functionalization with copper by cationic exchange with copper nitrate solutions at different concentrations. Elemental analysis highlighted a progressive increase of the amount of copper incorporated into the HA, reaching a maximum of ∼ 7 wt%. A combined X-ray diffraction and solid-state NMR investigation showed no significant structural differences after the Cu functionalization, confirming that the copper exchange occurs mainly at the surface until saturation and, for the higher Cu concentrations, also in the sub-surface/bulk layers of the material, without altering the HA crystal structure. The gradual substitution of surface Ca2+ by Cu2+ was studied also by IR spectroscopy using carbon monoxide as probe molecule. Finally, we assessed the catalytic activity of the materials testing the electrochemical reduction of H2O2 by cyclic voltammetry. We observed a progressive increase in catalytic activity correlated with the amount of Cu, suggesting the possible application of copper-exchanged HA as electrochemical H2O2 sensors.

Surface and structural characterization of Cu-exchanged hydroxyapatites and their application in H2O2 electrocatalytic reduction

G. Escolano Casado
First
;
P. Ivanchenko;L. Mino
Last
2022

Abstract

We report on the preparation of hydroxyapatite (HA) nanoparticles with high specific surface area, terminated with calcium-rich {0 1 0} facets, and their subsequent surface functionalization with copper by cationic exchange with copper nitrate solutions at different concentrations. Elemental analysis highlighted a progressive increase of the amount of copper incorporated into the HA, reaching a maximum of ∼ 7 wt%. A combined X-ray diffraction and solid-state NMR investigation showed no significant structural differences after the Cu functionalization, confirming that the copper exchange occurs mainly at the surface until saturation and, for the higher Cu concentrations, also in the sub-surface/bulk layers of the material, without altering the HA crystal structure. The gradual substitution of surface Ca2+ by Cu2+ was studied also by IR spectroscopy using carbon monoxide as probe molecule. Finally, we assessed the catalytic activity of the materials testing the electrochemical reduction of H2O2 by cyclic voltammetry. We observed a progressive increase in catalytic activity correlated with the amount of Cu, suggesting the possible application of copper-exchanged HA as electrochemical H2O2 sensors.
595
153495
153502
Copper-exchanged hydroxyapatites; electrocatalysis; electrochemical H; 2; O; 2; sensors; FTIR spectroscopy; solid-state NMR
G. Escolano Casado, P. Ivanchenko, G. Paul, C. Bisio, L. Marchese, A.M. Ashrafi, V. Milosavljevic, L. Degli Esposti, M. Iafisco, L. Mino
File in questo prodotto:
File Dimensione Formato  
Surface and structural characterization of Cu-exchanged hydroxyapatites-H2O2.pdf

Accesso riservato

Descrizione: PDF editoriale
Tipo di file: PDF EDITORIALE
Dimensione 1.4 MB
Formato Adobe PDF
1.4 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Cu HA_open access.pdf

Accesso aperto con embargo fino al 02/05/2024

Descrizione: Versione open access
Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 747.76 kB
Formato Adobe PDF
747.76 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1869719
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact