TY - JOUR

T1 - Sensitivity of nanocrystalline tungsten oxide to CO and ammonia gas determined by surface catalysts

AU - Marikutsa, Artem

AU - Yang, Lili

AU - Rumyantseva, Marina

AU - Batuk, Maria

AU - Hadermann, Joke

AU - Gaskov, Alexander

N1 - Funding Information: The work was financially supported by RFBR grant No. 16-53-76001 (RFBR – ERA.Net FONSENS 096). This work was supported in part by a grant from the St. Petersburg State University – Event 3-2018(id: 26520408). Publisher Copyright: © 2018 Elsevier B.V. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2018/12/20

Y1 - 2018/12/20

N2 - Nanocrystalline tungsten oxide with variable particle size and surface area was synthesized by aqueous deposition and heat treatment for use in resistive gas sensors. Surface modification with 1 wt.% Pd and Ru was performed by impregnation to improve the sensitivity to CO and ammonia. Acid and oxidation surface sites were evaluated by temperature-programmed techniques using probe molecules. The surface acidity dropped with increasing particle size, and was weakly affected by additives. Lower crystallinity of WO3 and the presence of Ru species favoured temperature-programmed reduction of the materials. Modifying WO3 increased its sensitivity, to CO at ambient condition for modification by Pd and to NH3 at elevated temperature for Ru modification. An in situ infrared study of the gas – solid interaction showed that the catalytic additives change the interaction route of tungsten oxide with the target gases and make the reception of detected molecules independent of the semiconductor oxide matrix.

AB - Nanocrystalline tungsten oxide with variable particle size and surface area was synthesized by aqueous deposition and heat treatment for use in resistive gas sensors. Surface modification with 1 wt.% Pd and Ru was performed by impregnation to improve the sensitivity to CO and ammonia. Acid and oxidation surface sites were evaluated by temperature-programmed techniques using probe molecules. The surface acidity dropped with increasing particle size, and was weakly affected by additives. Lower crystallinity of WO3 and the presence of Ru species favoured temperature-programmed reduction of the materials. Modifying WO3 increased its sensitivity, to CO at ambient condition for modification by Pd and to NH3 at elevated temperature for Ru modification. An in situ infrared study of the gas – solid interaction showed that the catalytic additives change the interaction route of tungsten oxide with the target gases and make the reception of detected molecules independent of the semiconductor oxide matrix.

KW - Ammonia

KW - Carbon monoxide

KW - Chemical modification

KW - Gas sensor

KW - Selectivity

KW - Tungsten oxide

UR - http://www.scopus.com/inward/record.url?scp=85053287842&partnerID=8YFLogxK

U2 - 10.1016/j.snb.2018.09.004

DO - 10.1016/j.snb.2018.09.004

M3 - Article

AN - SCOPUS:85053287842

VL - 277

SP - 336

EP - 346

JO - Sensors and Actuators, B: Chemical

JF - Sensors and Actuators, B: Chemical

SN - 0925-4005

ER -