TY  - JOUR
AU  - Vojisavljević, Katarina
AU  - Savić, Slavica
AU  - Počuča-Nešić, Milica
AU  - Hodžić, Aden
AU  - Kriechbaum, Manfred
AU  - Ribić, Vesna
AU  - Rečnik, Aleksander
AU  - Vukašinović, Jelena
AU  - Branković, Goran
AU  - Đokić, Veljko
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5919
AB  - Developing highly efficient semiconductor metal oxide (SMOX) sensors capable of accurate and fast responses to environmental humidity is still a challenging task. In addition to a not so pronounced sensitivity to relative humidity change, most of the SMOXs cannot meet the criteria of real-time humidity sensing due to their long response/recovery time. The way to tackle this problem is to control adsorption/desorption processes, i.e., water-vapor molecular dynamics, over the sensor’s active layer through the powder and pore morphology design. With this in mind, a KIT-5-mediated synthesis was used to achieve mesoporous tin (IV) oxide replica (SnO2-R) with controlled pore size and ordering through template inversion and compared with a sol-gel synthesized powder (SnO2-SG). Unlike SnO2-SG, SnO2-R possessed a high specific surface area and quite an open pore structure, similar to the KIT-5, as observed by TEM, BET and SWAXS analyses. According to TEM, SnO2-R consisted of fine-grained globular particles and some percent of exaggerated, grown twinned crystals. The distinctive morphology of the SnO2-R-based sensor, with its specific pore structure and an increased number of oxygen-related defects associated with the powder preparation process and detected at the sensor surface by XPS analysis, contributed to excellent humidity sensing performances at room temperature, comprised of a low hysteresis error (3.7%), sensitivity of 406.8 kΩ/RH% and swift response/recovery speed (4 s/6 s).
PB  - MDPI
T2  - Molecules
T1  - KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed
IS  - 4
SP  - 1754
VL  - 28
DO  - 10.3390/molecules28041754
ER  - 

@article{
author = "Vojisavljević, Katarina and Savić, Slavica and Počuča-Nešić, Milica and Hodžić, Aden and Kriechbaum, Manfred and Ribić, Vesna and Rečnik, Aleksander and Vukašinović, Jelena and Branković, Goran and Đokić, Veljko",
year = "2023",
abstract = "Developing highly efficient semiconductor metal oxide (SMOX) sensors capable of accurate and fast responses to environmental humidity is still a challenging task. In addition to a not so pronounced sensitivity to relative humidity change, most of the SMOXs cannot meet the criteria of real-time humidity sensing due to their long response/recovery time. The way to tackle this problem is to control adsorption/desorption processes, i.e., water-vapor molecular dynamics, over the sensor’s active layer through the powder and pore morphology design. With this in mind, a KIT-5-mediated synthesis was used to achieve mesoporous tin (IV) oxide replica (SnO2-R) with controlled pore size and ordering through template inversion and compared with a sol-gel synthesized powder (SnO2-SG). Unlike SnO2-SG, SnO2-R possessed a high specific surface area and quite an open pore structure, similar to the KIT-5, as observed by TEM, BET and SWAXS analyses. According to TEM, SnO2-R consisted of fine-grained globular particles and some percent of exaggerated, grown twinned crystals. The distinctive morphology of the SnO2-R-based sensor, with its specific pore structure and an increased number of oxygen-related defects associated with the powder preparation process and detected at the sensor surface by XPS analysis, contributed to excellent humidity sensing performances at room temperature, comprised of a low hysteresis error (3.7%), sensitivity of 406.8 kΩ/RH% and swift response/recovery speed (4 s/6 s).",
publisher = "MDPI",
journal = "Molecules",
title = "KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed",
number = "4",
pages = "1754",
volume = "28",
doi = "10.3390/molecules28041754"
}

Vojisavljević, K., Savić, S., Počuča-Nešić, M., Hodžić, A., Kriechbaum, M., Ribić, V., Rečnik, A., Vukašinović, J., Branković, G.,& Đokić, V.. (2023). KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed. in Molecules
MDPI., 28(4), 1754.
https://doi.org/10.3390/molecules28041754

Vojisavljević K, Savić S, Počuča-Nešić M, Hodžić A, Kriechbaum M, Ribić V, Rečnik A, Vukašinović J, Branković G, Đokić V. KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed. in Molecules. 2023;28(4):1754.
doi:10.3390/molecules28041754 .

Vojisavljević, Katarina, Savić, Slavica, Počuča-Nešić, Milica, Hodžić, Aden, Kriechbaum, Manfred, Ribić, Vesna, Rečnik, Aleksander, Vukašinović, Jelena, Branković, Goran, Đokić, Veljko, "KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed" in Molecules, 28, no. 4 (2023):1754,
https://doi.org/10.3390/molecules28041754 . .

TY  - CONF
AU  - Savić, Slavica M.
AU  - Vojisavljević, Katarina
AU  - Počuča-Nešić, Milica
AU  - Knežević, Nikola
AU  - Mladenović, Minja
AU  - Đokić, Veljko
AU  - Branković, Zorica
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6103
AB  - Over the past decade, the interest for fabrication of mesoporous metal oxides
has been increased, and that draw attention globally on fabrication and designing
efficient humidity sensors based on these materials. Their unique properties like
high surface area, large pore volume and interconnected pore channels provide
easier adsorption and facile transportation of water molecules across their surfaces.
Nanocasting as technique based on various silica hard templates is one of usually
utilized and efficient methods for processing of such materials.
Silica SBA-15 as a template is currently obtaining exclusive attention in
applications like photocatalysis, sensing, drug delivery and nanomaterials
fabrication since it has high surface area, pore volume, excellent thermal stability
and distinctive interconnectivity of its tunable pore channels. In this work, we used
SBA-15 as a hard template for production of SnO2 humidity sensor. SBA-15
assisted mesoporous SnO2 has been synthesized using incipient wet impregnation
process, consisting of two loading/calcination steps to fill up 15 % of the total pore
volume of template with SnO2, followed by template etching with 2M NaOH.
A few micron thick SnO2 film has been fabricated by applying the paste by the
doctor blade applicator onto alumina substrate provided with interdigitated Pt/Ag
electrodes. The sensor response of the film towards humidity was tested measuring
the change of the complex impedance of the sample exposed to a humid climate
chamber environment with the relative humidity, RH ranging from 40 % to 90 % at
25 °C and from 30 % to 90 % at 50 °C. This study demonstrated that nanocast SnO2
possesses sufficient quality to be used as a material for fabrication of high
performance humidity sensors.
PB  - Belgrade : Institute for Multidisciplinary Research
C3  - Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
T1  - SBA-15 Assisted SnO2 Humidity Sensor
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6103
ER  - 

@conference{
author = "Savić, Slavica M. and Vojisavljević, Katarina and Počuča-Nešić, Milica and Knežević, Nikola and Mladenović, Minja and Đokić, Veljko and Branković, Zorica",
year = "2019",
abstract = "Over the past decade, the interest for fabrication of mesoporous metal oxides
has been increased, and that draw attention globally on fabrication and designing
efficient humidity sensors based on these materials. Their unique properties like
high surface area, large pore volume and interconnected pore channels provide
easier adsorption and facile transportation of water molecules across their surfaces.
Nanocasting as technique based on various silica hard templates is one of usually
utilized and efficient methods for processing of such materials.
Silica SBA-15 as a template is currently obtaining exclusive attention in
applications like photocatalysis, sensing, drug delivery and nanomaterials
fabrication since it has high surface area, pore volume, excellent thermal stability
and distinctive interconnectivity of its tunable pore channels. In this work, we used
SBA-15 as a hard template for production of SnO2 humidity sensor. SBA-15
assisted mesoporous SnO2 has been synthesized using incipient wet impregnation
process, consisting of two loading/calcination steps to fill up 15 % of the total pore
volume of template with SnO2, followed by template etching with 2M NaOH.
A few micron thick SnO2 film has been fabricated by applying the paste by the
doctor blade applicator onto alumina substrate provided with interdigitated Pt/Ag
electrodes. The sensor response of the film towards humidity was tested measuring
the change of the complex impedance of the sample exposed to a humid climate
chamber environment with the relative humidity, RH ranging from 40 % to 90 % at
25 °C and from 30 % to 90 % at 50 °C. This study demonstrated that nanocast SnO2
possesses sufficient quality to be used as a material for fabrication of high
performance humidity sensors.",
publisher = "Belgrade : Institute for Multidisciplinary Research",
journal = "Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia",
title = "SBA-15 Assisted SnO2 Humidity Sensor",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6103"
}

Savić, S. M., Vojisavljević, K., Počuča-Nešić, M., Knežević, N., Mladenović, M., Đokić, V.,& Branković, Z.. (2019). SBA-15 Assisted SnO2 Humidity Sensor. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
Belgrade : Institute for Multidisciplinary Research..
https://hdl.handle.net/21.15107/rcub_technorep_6103

Savić SM, Vojisavljević K, Počuča-Nešić M, Knežević N, Mladenović M, Đokić V, Branković Z. SBA-15 Assisted SnO2 Humidity Sensor. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia. 2019;.
https://hdl.handle.net/21.15107/rcub_technorep_6103 .

Savić, Slavica M., Vojisavljević, Katarina, Počuča-Nešić, Milica, Knežević, Nikola, Mladenović, Minja, Đokić, Veljko, Branković, Zorica, "SBA-15 Assisted SnO2 Humidity Sensor" in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia (2019),
https://hdl.handle.net/21.15107/rcub_technorep_6103 .

TY  - CONF
AU  - Vojisavljević, Katarina
AU  - Savić, Slavica M.
AU  - Počuča-Nešić, Milica
AU  - Đokić, Veljko
AU  - Ribić, Vesna
AU  - Branković, Zorica
AU  - Branković, Goran
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6106
AB  - In this contribution, the mesoporous SnO2 was fabricated via nanocasting,
where the hydrothermally processed silica KIT-5 with a high specific surface area of
610 m2/g and pore volume of 0.72 cm3/g was used as a hard template. Following the
two precursor loading/calcination steps of the wet impregnation process, the
appropriate amount of the Sn- precursor solution was used to fill up 15 % of the total
pore volume of the silica template with SnO2. This synthesis route with a template
etching by 2M NaOH solution resulted in nanocast SnO2 with Brunauer-EmmettTeller specific surface area of 33 m2
/g, where SnO2 nanoparticles of 8–10 nm
formed the ordered domains along with fractions of disordered regions, as confirmed
by the transmission electron microscopy (TEM). Based on the Barrett-Joyner-Halenda model from the desorption branch of the N2 adsorption/desorption isotherms, the pore size of SnO2 is centered at 8.6 nm, demonstrating quite open and accessible pore structure of the material. Wide-angle X-ray diffraction (XRD) measurement confirmed the formation of the tetragonal SnO2 phase. Because of the low Si content after the template etching (< 0.5%, confirmed by EDS analysis),
formation of substantial amounts of SnSiO3 can be excluded, and no evidence for
such phase was found in the XRD.
The as prepared SnO2 nanocast was further used to fabricate a few micron thick
film by the doctor blade technique on alumina substrate provided with interdigitated
Pt/Ag electrodes. The sensor response of the film towards humidity was tested
measuring the change of the complex impedance of the sample exposed to a humid
climate chamber environment with the relative humidity (RH) ranging from 40% to
90% at 25 °C and from 30% to 90% at 50 °C. The value of impedance measured at
100 Hz and 25 oC was reduced 132 times within the RH range of 40 % to 90 %,
while it tended to decrease in a moderate manner at 50 °C under the same frequency
and RH range. The film exhibited remarkably rapid response (4 s) and quick
recovery time (6 s) when exposed to RH change from 37% to 90% at 25 °C. Such a
fast response/recovery time and relatively low hysteresis of 4% observed under 50
% RH and 25 °C indicate the promising potentials of nanocasted SnO2 to be used as
an active layer for humidity sensors.
PB  - Belgrade : Institute for Multidisciplinary Research
C3  - Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
T1  - Humidity Sensor Based on Mesoporous SnO2 Fabricated via Nanocasting Technique
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6106
ER  - 

@conference{
author = "Vojisavljević, Katarina and Savić, Slavica M. and Počuča-Nešić, Milica and Đokić, Veljko and Ribić, Vesna and Branković, Zorica and Branković, Goran",
year = "2019",
abstract = "In this contribution, the mesoporous SnO2 was fabricated via nanocasting,
where the hydrothermally processed silica KIT-5 with a high specific surface area of
610 m2/g and pore volume of 0.72 cm3/g was used as a hard template. Following the
two precursor loading/calcination steps of the wet impregnation process, the
appropriate amount of the Sn- precursor solution was used to fill up 15 % of the total
pore volume of the silica template with SnO2. This synthesis route with a template
etching by 2M NaOH solution resulted in nanocast SnO2 with Brunauer-EmmettTeller specific surface area of 33 m2
/g, where SnO2 nanoparticles of 8–10 nm
formed the ordered domains along with fractions of disordered regions, as confirmed
by the transmission electron microscopy (TEM). Based on the Barrett-Joyner-Halenda model from the desorption branch of the N2 adsorption/desorption isotherms, the pore size of SnO2 is centered at 8.6 nm, demonstrating quite open and accessible pore structure of the material. Wide-angle X-ray diffraction (XRD) measurement confirmed the formation of the tetragonal SnO2 phase. Because of the low Si content after the template etching (< 0.5%, confirmed by EDS analysis),
formation of substantial amounts of SnSiO3 can be excluded, and no evidence for
such phase was found in the XRD.
The as prepared SnO2 nanocast was further used to fabricate a few micron thick
film by the doctor blade technique on alumina substrate provided with interdigitated
Pt/Ag electrodes. The sensor response of the film towards humidity was tested
measuring the change of the complex impedance of the sample exposed to a humid
climate chamber environment with the relative humidity (RH) ranging from 40% to
90% at 25 °C and from 30% to 90% at 50 °C. The value of impedance measured at
100 Hz and 25 oC was reduced 132 times within the RH range of 40 % to 90 %,
while it tended to decrease in a moderate manner at 50 °C under the same frequency
and RH range. The film exhibited remarkably rapid response (4 s) and quick
recovery time (6 s) when exposed to RH change from 37% to 90% at 25 °C. Such a
fast response/recovery time and relatively low hysteresis of 4% observed under 50
% RH and 25 °C indicate the promising potentials of nanocasted SnO2 to be used as
an active layer for humidity sensors.",
publisher = "Belgrade : Institute for Multidisciplinary Research",
journal = "Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia",
title = "Humidity Sensor Based on Mesoporous SnO2 Fabricated via Nanocasting Technique",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6106"
}

Vojisavljević, K., Savić, S. M., Počuča-Nešić, M., Đokić, V., Ribić, V., Branković, Z.,& Branković, G.. (2019). Humidity Sensor Based on Mesoporous SnO2 Fabricated via Nanocasting Technique. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
Belgrade : Institute for Multidisciplinary Research..
https://hdl.handle.net/21.15107/rcub_technorep_6106

Vojisavljević K, Savić SM, Počuča-Nešić M, Đokić V, Ribić V, Branković Z, Branković G. Humidity Sensor Based on Mesoporous SnO2 Fabricated via Nanocasting Technique. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia. 2019;.
https://hdl.handle.net/21.15107/rcub_technorep_6106 .

Vojisavljević, Katarina, Savić, Slavica M., Počuča-Nešić, Milica, Đokić, Veljko, Ribić, Vesna, Branković, Zorica, Branković, Goran, "Humidity Sensor Based on Mesoporous SnO2 Fabricated via Nanocasting Technique" in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia (2019),
https://hdl.handle.net/21.15107/rcub_technorep_6106 .