TY - JOUR
T1 - Optical properties of copper clusters in zeolite 4A with surface enhanced Raman spectroscopy applications
AU - Leal-Perez, J. E.
AU - Flores-Valenzuela, J.
AU - Cortez-Valadez, M.
AU - Hurtado-Macías, A.
AU - Vargas-Ortiz, R. A.
AU - Bocarando-Chacon, J. G.
AU - Almaral-Sánchez, J. L.
N1 - Publisher Copyright:
© 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
PY - 2022/8
Y1 - 2022/8
N2 - In this study, we used the ion exchange properties of zeolite 4A to stabilize copper ionic species. These species showed absorption bands in the ultraviolet region between 210 and 320 nm. Complementarily, DFT (Density-Functional Theory) at different levels of approximation was employed in combination with the LANL2DZ (Los Alamos National Laboratory 2 double zeta) and SDD (Stuttgart/Dresden) basis sets to find hints of optical absorption behavior associated with electronic transitions. The copper clusters in ZA were evaluated as SERS (Surface-Enhanced Raman Spectroscopy) substrate using pyridine (Py) and methylene blue (MB) molecules. Additionally, molecular descriptors as electron transfer factor, electronegativity and global hardness were considered to study the charge transfer between the molecular systems and the ionic copper species. The DFT calculations suggest that the Cu3+ cluster manifests optically. The molecular descriptors allowed to identify the effect of charge transfer from the analyte to the cluster, specifically toward the LUMO or higher energy orbitals, and the systems obtained showed capacity as SERS substrates, evaluated on Py and MB.
AB - In this study, we used the ion exchange properties of zeolite 4A to stabilize copper ionic species. These species showed absorption bands in the ultraviolet region between 210 and 320 nm. Complementarily, DFT (Density-Functional Theory) at different levels of approximation was employed in combination with the LANL2DZ (Los Alamos National Laboratory 2 double zeta) and SDD (Stuttgart/Dresden) basis sets to find hints of optical absorption behavior associated with electronic transitions. The copper clusters in ZA were evaluated as SERS (Surface-Enhanced Raman Spectroscopy) substrate using pyridine (Py) and methylene blue (MB) molecules. Additionally, molecular descriptors as electron transfer factor, electronegativity and global hardness were considered to study the charge transfer between the molecular systems and the ionic copper species. The DFT calculations suggest that the Cu3+ cluster manifests optically. The molecular descriptors allowed to identify the effect of charge transfer from the analyte to the cluster, specifically toward the LUMO or higher energy orbitals, and the systems obtained showed capacity as SERS substrates, evaluated on Py and MB.
KW - Chemical enhancement mechanism
KW - Copper ions
KW - Theoretical and experimental analysis
KW - Zeolite 4A
UR - http://www.scopus.com/inward/record.url?scp=85133726680&partnerID=8YFLogxK
U2 - 10.1007/s00339-022-05785-6
DO - 10.1007/s00339-022-05785-6
M3 - Artículo
AN - SCOPUS:85133726680
SN - 0947-8396
VL - 128
JO - Applied Physics A: Materials Science and Processing
JF - Applied Physics A: Materials Science and Processing
IS - 8
M1 - 649
ER -