TY - JOUR
T1 - In-situ monitoring by thermal lens microscopy of a photocatalytic reduction process of hexavalent chromium
AU - Cedeño, E.
AU - Plazas-Saldaña, J.
AU - Gordillo-Delgado, F.
AU - Bedoya, A.
AU - Marín, E.
N1 - Publisher Copyright:
© 2019 Revista Mexicana de Física.
PY - 2018
Y1 - 2018
N2 - In this work, we describe the application of a micro-spatial thermal lens spectroscopy setup (thermal lens microscope, TLM) with coaxial counter-propagating pump, and probe laser beams, and an integrated passive optical Fabry-Perot, to quantify the Cr-VI concentration in water during a photocatalytic reaction in-situ. A series of test samples was analyzed using the 1.5 diphenil carbazide colorimetric method. A calibration curve was obtained by plotting of the TLM signal as a function of the concentration of Cr(VI) in a range between 0 and 10 μg/L (1 μg/L = 1 ppb, part per billion), with a detection limit of 53 ng/L (1 ng/L = 1 ppt, part per trillion). A solution of 10 μg/L Cr(VI) in distillated water was placed into a cell in contact with an iron-incorporated titanium dioxide film, which was previously grown onto a 1 mm thick glass microscope slide by the sol-gel dip-coating technique. The TLM signal was registered as a function of the photocatalysis time measured from the beginning of the process, radiating the film with UV-violet light. The Cr(VI) concentration was determined with the calibration curve and after the first 50 minutes a reduction of 95 % of Cr(VI) was observed, being the chemical reaction kinetic described by a potential time decreasing function.
AB - In this work, we describe the application of a micro-spatial thermal lens spectroscopy setup (thermal lens microscope, TLM) with coaxial counter-propagating pump, and probe laser beams, and an integrated passive optical Fabry-Perot, to quantify the Cr-VI concentration in water during a photocatalytic reaction in-situ. A series of test samples was analyzed using the 1.5 diphenil carbazide colorimetric method. A calibration curve was obtained by plotting of the TLM signal as a function of the concentration of Cr(VI) in a range between 0 and 10 μg/L (1 μg/L = 1 ppb, part per billion), with a detection limit of 53 ng/L (1 ng/L = 1 ppt, part per trillion). A solution of 10 μg/L Cr(VI) in distillated water was placed into a cell in contact with an iron-incorporated titanium dioxide film, which was previously grown onto a 1 mm thick glass microscope slide by the sol-gel dip-coating technique. The TLM signal was registered as a function of the photocatalysis time measured from the beginning of the process, radiating the film with UV-violet light. The Cr(VI) concentration was determined with the calibration curve and after the first 50 minutes a reduction of 95 % of Cr(VI) was observed, being the chemical reaction kinetic described by a potential time decreasing function.
KW - Hexavalent chromium
KW - Photocatalysis
KW - Thermal lens microscopy
KW - Titanium dioxide
UR - http://www.scopus.com/inward/record.url?scp=85106838155&partnerID=8YFLogxK
U2 - 10.31349/REVMEXFIS.64.507
DO - 10.31349/REVMEXFIS.64.507
M3 - Artículo
AN - SCOPUS:85106838155
SN - 0035-001X
VL - 64
SP - 507
EP - 511
JO - Revista Mexicana de Fisica
JF - Revista Mexicana de Fisica
IS - 5
ER -