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Bjorklund, Robert
Alternative names
Publications (10 of 24) Show all publications
Huotari, J., Lappalainen, J., Eriksson, J., Bjorklund, R., Heinonen, E., Miinalainen, I., . . . Lloyd Spetz, A. (2016). Synthesis of nanostructured solid-state phases of V7O16 and V2O5 compounds for ppb-level detection of ammonia. Journal of Alloys and Compounds, 675, 433-440
Open this publication in new window or tab >>Synthesis of nanostructured solid-state phases of V7O16 and V2O5 compounds for ppb-level detection of ammonia
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2016 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 675, p. 433-440Article in journal (Refereed) Published
Abstract [en]

Solid state phase of V7O16 with separate V2O5 phase were fabricated by pulsed laser deposition. The crystal structure and symmetry of the deposited films were studied with X-ray diffraction and Raman spectroscopy, respectively. Rietveld analysis was performed to the X-ray diffraction measurement results. The surface potentials and morphologies of the films were studied with atomic force microscopy, and microstructure of the thin films was analysed by transmission electron microscopy. Raman spectroscopy and Rietveld refinement results confirmed that the thin-film crystal structures varied between orthorombic V2O5 phase and another phase, triclinic V2016, previously found only in the walls of vanadium oxide nanotubes (VOx, -NT), bound together with organic amine. We have earlier presented the first results of stable and pure metal -oxide solid-state phase of V2016 manufactured from ceramic V205 target. Here we show more detailed study of these structures. The microstructure studies showed a variation on the porosity of the films according to crystal structures and also some fibre -like nanostructures were found in the films. The surface morphology depended strongly on the crystal structure and the surface potential studies showed 50 meV difference in the work function values between the phases. Compounds were found to be extremely sensitive towards ammonia, NH3, down to 40 ppb concentrations, and have shown to have the stability and selectivity to control the Selective Catalytic Reduction process, where nitrogen oxides are reduced by ammonia in, e.g. diesel exhausts.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE SA, 2016
Keywords
Vanadium oxides; Mixed phase; V7O16; V2O5; Thin film
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-127542 (URN)10.1016/j.jallcom.2016.03.116 (DOI)000373614400059 ()
Note

Funding Agencies|Finnish Funding Agency for Innovations - TEKES project CHEMPACK [1427/31/2010]; Tauno Tonning foundation; Henry Ford foundation; Ulla Tuominen Foundation; Riitta and Jorma J. Takanen foundation; Swedish Research Council

Available from: 2016-05-04 Created: 2016-05-03 Last updated: 2017-11-30
Huotari, J., Bjorklund, R., Lappalainen, J. & Lloyd Spetz, A. (2015). Pulsed Laser Deposited Nanostructured Vanadium Oxide Thin Films Characterized as Ammonia Sensors. Sensors and actuators. B, Chemical, 217, 22-29
Open this publication in new window or tab >>Pulsed Laser Deposited Nanostructured Vanadium Oxide Thin Films Characterized as Ammonia Sensors
2015 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 217, p. 22-29Article in journal (Refereed) Published
Abstract [en]

Vanadium oxide thin films were fabricated by pulsed laser deposition. The microstructure and crystal symmetry of the deposited films were studied with X-ray diffraction, scanning electron microscopy (SEM), and Raman spectroscopy, respectively. The films surface morphology was examined by atomic force microscopy. Raman spectroscopy and XRD results showed that the thin film phase-structure was composed of pure orthorhombic V2O5 phase, or they had a mixed phase structure of orthorhombic V2O5 and triclinic V7O16. Surface morphology of the films consisted of nanosized particles, although in pure V2O5 films some bigger agglomerates and flakes were also seen. The conductivity based gas sensing measurements showed a clear response already at ppb-levels of NH3 and strong selectivity to ammonia was found when compared to NO and CO gases. Also, the films showed promising gas sensing behavior in cross-sensitivity measurements between NO and NH3, being able to sense ammonia even in the presence of NO. This is an important property when considering possible sensing applications to control Selective Catalytic Reduction processes, e.g. in diesel engine exhausts, where introduced ammonia, or urea, transforms nitrogen oxide gases in a catalytic converter to nitrogen and water. (C) 2015 Elsevier B.V. All rights reserved.

Place, publisher, year, edition, pages
Elsevier, 2015
Keywords
Vanadium oxides; Mixed phase; V7O16; V2O5; Thin film; NH3; Gas sensor
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-120028 (URN)10.1016/j.snb.2015.02.089 (DOI)000355919200004 ()
Note

Funding Agencies|Finnish Funding Agency for Innovations - TEKES project CHEMPACK [1427/31/2010]; Riitta and Jorma J. Takanen Foundation; Walter Ahlstrom Foundation

Available from: 2015-07-06 Created: 2015-07-06 Last updated: 2017-12-04
Huotari, J., Bjorklund, R., Lappalainen, J. & Lloyd Spetz, A. (2014). Vanadium Oxide Thin Films as Ammonia Sensing Material. In: Proc. of IMCS 2014, Buenos Aires, Argentina, March 17-19: . Paper presented at IMCS 2014, Buenos Aires, Argentina, March 17-19.
Open this publication in new window or tab >>Vanadium Oxide Thin Films as Ammonia Sensing Material
2014 (English)In: Proc. of IMCS 2014, Buenos Aires, Argentina, March 17-19, 2014Conference paper, Oral presentation with published abstract (Refereed)
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-113313 (URN)
Conference
IMCS 2014, Buenos Aires, Argentina, March 17-19
Available from: 2015-01-15 Created: 2015-01-15 Last updated: 2015-01-22
Huotari, J., Cao, W., Bjorklund, R., Niu, Y., Pankratov, V., Lappalainen, J., . . . Huttula, M. (2014). X-ray and Raman Spectroscopy Studies of Vanadium Oxide Thin Films Used as Ammonia Sensors. In: Proc. E-MRS 2014, Lille, France, May 26-30: . Paper presented at E-MRS 2014, Lille, France, May 26-30.
Open this publication in new window or tab >>X-ray and Raman Spectroscopy Studies of Vanadium Oxide Thin Films Used as Ammonia Sensors
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2014 (English)In: Proc. E-MRS 2014, Lille, France, May 26-30, 2014Conference paper, Oral presentation with published abstract (Refereed)
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-113324 (URN)
Conference
E-MRS 2014, Lille, France, May 26-30
Available from: 2015-01-15 Created: 2015-01-15 Last updated: 2015-01-22
Lloyd Spetz, A., Huotari, J., Bur, C., Bjorklund, R., Lappalainen, J., Jantunen, H., . . . Andersson, M. (2013). Chemical sensor systems for emission control from combustions. Sensors and actuators. B, Chemical, 187(SI), 184-190
Open this publication in new window or tab >>Chemical sensor systems for emission control from combustions
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2013 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 187, no SI, p. 184-190Article in journal (Refereed) Published
Abstract [en]

Environmental and health concern has increased the importance to monitor and control emissions like toxic gases and particulate matter from combustion processes. The silicon carbide-field effect transistor (SiC-FET) technology offers versatile and powerful sensors for gas detection also in combination with combustion of particles. Emission control has been demonstrated e. g. for small and medium sized power plants and diesel exhausts. The potential danger of nanoparticles makes such detectors interesting not only for detection of concentration and size of particles but also detection of the content of particles. Due to the possibility of operating the sensor devices in different independent modes (e. g. temperature- and bias-modulated) the SiC-FET technology also lends itself for the future development of sensor adaptation, self-diagnosis and auto calibration, which is expected to improve the performance of such a combined gas/particle sensor system. Here we report progress on the sensor technology itself, the application of a sensor system as an alarm for ammonia emission and preliminary results of particle detection in diesel exhausts and particles from a power plant and a steel plant.

Place, publisher, year, edition, pages
Elsevier, 2013
Keywords
SiC FET Gas sensor Particle detector Alarm Data evaluation
National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:liu:diva-92401 (URN)10.1016/j.snb.2012.10.078 (DOI)000324298300029 ()
Available from: 2013-05-10 Created: 2013-05-10 Last updated: 2017-12-06
Lloyd Spetz, A., Darmastuti, Z., Bur, C., Huotari, J., Bjorklund, R., Lindqvist, N., . . . Andersson, M. (2013). Chemical sensor systems for environmental and emission control. In: Proc. SPIE Defence, Security + Sensors: . Paper presented at Micro- and Nanotechnology Sensors, Systems, and Applications V Conference; Baltimore, MD; United States.
Open this publication in new window or tab >>Chemical sensor systems for environmental and emission control
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2013 (English)In: Proc. SPIE Defence, Security + Sensors, 2013Conference paper, Published paper (Refereed)
Abstract [en]

Focusing on environment and health aspects, the importance of monitoring and controlling dangerous gases and particulate matter increases. For this purpose we present a new version of silicon carbide based gas sensors with improved properties and suitable for high temperature and harsh environments such as power plants or car exhausts. Development of sulfur dioxide sensors for a power plant application is described as well as sensors for detection of ammonia in connection with the SCR process where urea is converted to ammonia, which reduces nitric oxide components in the exhausts. We also describe progress on nanoparticle detection, especially related to detection of the content of adsorbed particles through heating and detection of emitted molecules by a sensor array. Some results are also presented from impedance spectroscopy for detection of the concentration of nanoparticles but with the potential to reveal more details about the particles such as shape and kind of particles. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:liu:diva-92406 (URN)10.1117/12.2016795 (DOI)000325263900015 ()
Conference
Micro- and Nanotechnology Sensors, Systems, and Applications V Conference; Baltimore, MD; United States
Note

Invited talk, Lloyd Spetz

Available from: 2013-05-11 Created: 2013-05-10 Last updated: 2017-11-07
Lloyd Spetz, A., Darmastuti, Z., Bjorklund, R., Andersson, M., Bur, C., Schütze, A., . . . Lindqvist, N. (2013). Improved chemical sensors track and control emissions. SPIE - International Society for Optical Engineering
Open this publication in new window or tab >>Improved chemical sensors track and control emissions
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2013 (English)Other (Other (popular science, discussion, etc.))
Abstract [en]

Sensitive, low-cost silicon carbide-based gas sensors can detect toxic emissions and hazardous nanoparticulate matter in previously untenable environments.

Place, publisher, year, pages
SPIE - International Society for Optical Engineering, 2013
National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:liu:diva-92459 (URN)10.1117/2.1201304.004839 (DOI)
Note

SPIE Newsroom

Available from: 2013-05-11 Created: 2013-05-11 Last updated: 2014-01-09
Larsson, A., Storstrom, O., Tollefsen Seip, T., Hjelstuen, M., Bjorklund, R., Lloyd Spetz, A., . . . Hammarlund, L. (2012). Thermal Management System for Particle Sensors Design, Performance and Verification. IEEE Sensors Journal, 12(6), 2299-2305
Open this publication in new window or tab >>Thermal Management System for Particle Sensors Design, Performance and Verification
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2012 (English)In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 12, no 6, p. 2299-2305Article in journal (Refereed) Published
Abstract [en]

This paper presents the thermal performance of a proposed thermal management device (patented in 2009) intended for a thermophoresis-based soot sensor. The performance was studied for temperatures ranging from 50 to 400 degrees C and for exhaust speeds up to 10 m/s. It also presents the design and basic concepts. The performance study and design development were performed with finite element analysis (FEA). The FEA results were then verified with experiments in a heated wind tunnel. The relative performance of the device was found to increase for higher temperatures and lower wind speeds. The main conclusion drawn from this paper was that it is feasible to cool a sensor surface enough for a thermophoresis-based soot sensor in a diesel exhaust system.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2012
Keywords
Exhaust monitoring, finite element analysis (FEA), soot sensor, thermal management, thermophoresis
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-77857 (URN)10.1109/JSEN.2012.2185044 (DOI)000303502900014 ()
Note
Funding Agencies|Nordic Innovation Centre, Oslo, Norway|09044I VINNOVA|Swedish Agency for Research and Innovation, Stockholm, Sweden|2009-02887|VINN Excellence Centre FunMat||Functional Nanoscale Materials, Linkoping University||Available from: 2012-05-31 Created: 2012-05-31 Last updated: 2017-12-07
Malik, A., Abdulhamid, H., Pagels, J., Rissler, J., Lindskog, M., Nilsson, P., . . . Sanati, M. (2011). A Potential Soot Mass Determination Method from Resistivity Measurement of Thermophoretically Deposited Soot. AEROSOL SCIENCE AND TECHNOLOGY, 45(2), 284-294
Open this publication in new window or tab >>A Potential Soot Mass Determination Method from Resistivity Measurement of Thermophoretically Deposited Soot
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2011 (English)In: AEROSOL SCIENCE AND TECHNOLOGY, ISSN 0278-6826, Vol. 45, no 2, p. 284-294Article in journal (Refereed) Published
Abstract [en]

Miniaturized detection systems for nanometer-sized airborne particles are in demand, for example in applications for onboard diagnostics downstream particulate filters in modern diesel engines. A soot sensor based on resistivity measurements was developed and characterized. This involved generation of soot particles using a quenched co-flow diffusion flame; depositing the particles onto a sensor substrate using thermophoresis and particle detection using a finger electrode structure, patterned on thermally oxidized silicon substrate. The generated soot particles were characterized using techniques including Scanning Mobility Particle Sizer for mobility size distributions, Differential Mobility Analyzer-Aerosol Particle Mass analyzer for the mass-mobility relationship, and Transmission Electron Microscopy for morphology. The generated particles were similar to particles from diesel engines in concentration, mobility size distribution, and mass fractal dimension. The primary particle size, effective density and organic mass fraction were slightly lower than values reported for diesel engines. The response measured with the sensors was largely dependent on particle mass concentration, but increased with increasing soot aggregate mobility size. Detection down to cumulative mass as small as 20-30 mu g has been demonstrated. The detection limit can be improved by using a more sensitive resistance meter, modified deposition cell, larger flow rates of soot aerosol and modifying the sensor surface.

Place, publisher, year, edition, pages
Taylor and Francis, 2011
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-64582 (URN)10.1080/02786826.2010.533214 (DOI)000285543700012 ()
Note
This is an electronic version of an article published in: A Malik, H Abdulhamid, J Pagels, J Rissler, M Lindskog, P Nilsson, Robert Bjorklund, P Jozsa, J Visser, Anita Lloyd Spetz and M Sanati, A Potential Soot Mass Determination Method from Resistivity Measurement of Thermophoretically Deposited Soot, 2011, AEROSOL SCIENCE AND TECHNOLOGY, (45), 2, 284-294. AEROSOL SCIENCE AND TECHNOLOGY is available online at informaworldTM: http://dx.doi.org/10.1080/02786826.2010.533214 Copyright: Taylor & Francis http://www.tandf.co.uk/journals/default.asp Available from: 2011-01-28 Created: 2011-01-28 Last updated: 2014-01-09
Iqbal, Z. & Bjorklund, R. B. (2011). Assessment of a mobile phone for use as a spectroscopic analytical tool for foods and beverages. International journal of food science & technology, 46(11), 2428-2436
Open this publication in new window or tab >>Assessment of a mobile phone for use as a spectroscopic analytical tool for foods and beverages
2011 (English)In: International journal of food science & technology, ISSN 0950-5423, E-ISSN 1365-2621, Vol. 46, no 11, p. 2428-2436Article in journal (Refereed) Published
Abstract [en]

A mobile phone was used to perform optical analyses of foods and beverages. The phone’s screen served as illumination source and front view camera recorded images. Reflected intensities were used to discriminate among the different samples analysed by principal component analysis. Samples studied illustrated the technique’s potential analytical capabilities with respect to adulteration and authenticity. Three coloured additives (red, green and blue) in the concentration range 2-10 mg/l in a lemon lime beverage were discriminated. Adulteration by up to 25% water of milk with 3% fat content was detected with an estimated detection limit of about 3% water. Changes occurring on a green onion surface over a 48 h aging period at room temperature were monitored. Five different cuts from lamb carcasses weighing 9 and 14 kg were classified by the method. Considerable additional work with regard to sampling, data treatment and quantifying results is necessary before the goal of using the technique as a point of purchase analytical tool can be realised.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2011
Keywords
Mobile phone, point of purchase, adulteration, authenticity, colourants, milk, vegetable freshness, meat cuts, multivariate analysis
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-70849 (URN)10.1111/j.1365-2621.2011.02766.x (DOI)000296377300027 ()
Note
Funding agencies|Pakistans Higher Education Commission (HEC)||Available from: 2011-09-20 Created: 2011-09-20 Last updated: 2017-12-08Bibliographically approved
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