Tag Archives: Scanning Probe Microscopy

Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials

NANOSENSORS™ conductive diamond coated  CDT-NCLR AFM probes were used for the piezoresponse force microscopy ( PFM ) on non-piezoelectric dielectrics described in this brand new publication: “Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials” by Amir Abdollahi et al.

The autors show theoretically and experimentally, that large effective piezoelectric coefficients can be measured in non-piezoelectric dielectrics due to converse flexoelectricity.*

Figure 4 from “Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials” by Amir Abdollahi et al.: Study of converse flexoelectricity induced at the tip apex of an atomic force microscope cantilever as a function of the applied force. a Effective piezoelectric coefficient as a function of applied force for the SrTiO3 crystal. Filled squares correspond to the values obtained after the simulation. Empty circles correspond to the experimental values obtained with a NANOSENSORS CDT-FM AFM tip with a cantilever of medium stiffness (k ≈ 2.8 Nm−1) coated with doped diamond. The error bars correspond to the error of the linear fitting of the experimental data, which correlates the measured electromechanical amplitude of oscillation Δh with the Vac applied voltage. b The effective contact radius a scales with the force, and is determined by the tip radius. The experimental tip radius is obtained after the measurement of the nanoscale electromechanical response from the scanning electron microscopy image of the used tip. In this case, the tip radius of the diamond coated tip is 105 nm, and is observed to keep a spherical shape after the measurements
Figure 4 from “Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials” by Amir Abdollahi et al.:
Study of converse flexoelectricity induced at the tip apex of an atomic force microscope cantilever as a function of the applied force. a Effective piezoelectric coefficient as a function of applied force for the SrTiO3 crystal. Filled squares correspond to the values obtained after the simulation. Empty circles correspond to the experimental values obtained with a Nanosensors CDT-FMR tip with a cantilever of medium stiffness (k ≈ 2.8 Nm−1) coated with doped diamond. The error bars correspond to the error of the linear fitting of the experimental data, which correlates the measured electromechanical amplitude of oscillation Δh with the Vac applied voltage. b The effective contact radius a scales with the force, and is determined by the tip radius. The experimental tip radius is obtained after the measurement of the nanoscale electromechanical response from the scanning electron microscopy image of the used tip. In this case, the tip radius of the diamond coated tip is 105 nm, and is observed to keep a spherical shape after the measurements

*Amir Abdollahi, Neus Domingo, Irene Arias, Gustau Catalan
Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials
Nature Communicationsvolume 10, Article number: 1266 (2019)
DOI: https://doi.org/10.1038/s41467-019-09266-y

Please refer to this external link for the full article: https://www.nature.com/articles/s41467-019-09266-y

Open Access The article «Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials» by Amir Abdollahi et al. is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

 

Get free NANOSENSORS qp-fast AFM probes at booth 836 at ACS Orlando 2019

Are you looking for AFM probes with unsurpassed small variation in spring constant and resonance frequency? Then visit our colleagues @NanoAndMore USA booth no. 836 @AmerChemSociety National Meeting & Expo 2019 in Orlando, Florida this week and get your free sample of NANOSENSORS™ uniqprobe qp-fast AFM probes

NANOSENSORS uniqprobe qp-fast AFM probe
NANOSENSORS uniqprobe qp-fast AFM probe

Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2

Engineering chlorophyll (Chl) pigments that are bound to photosynthetic light-harvesting proteins is one promising strategy to regulate spectral coverage for photon capture and to improve the photosynthetic efficiency of these proteins.*

The in situ oxidation of BChl a in light-harvesting protein LH2 from a purple bacterium Rhodoblastus acidophilus by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone demonstrated in the article “Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2” by Yoshitaka Saga et al. will be useful for engineering photofunctions in natural light-harvesting proteins and for understanding the alteration from BChl pigments in anoxygenic photosynthetic bacteria to Chl pigments in oxygenic organisms in the evolution of photosynthesis.*

The authors observed their sample in 20 mM Tris buffer containing 150 mM NaCl (pH 8.0) using a  home-built frequency modulation AFM ( FM-AFM ) with NANOSENSORS™ PPP-NCHAuD AFM probes.*

Figure 6 from «Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2” by Y. Saga et al.: FM-AFM images of native LH2 (A) and oxidized LH2 (B) adsorbed on mica taken in 20 mM Tris buffer containing 150 mM NaCl (pH 8.0). Left: wide images. Middle: locally enlarged images of single LH2 proteins. Right: overlapped height-profiles of ten proteins. NANOSENSORS PPP-NCHAuD AFM probes were used.
Figure 6 from «Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2” by Y. Saga et al.: FM-AFM images of native LH2 (A) and oxidized LH2 (B) adsorbed on mica taken in 20 mM Tris buffer containing 150 mM NaCl (pH 8.0). Left: wide images. Middle: locally enlarged images of single LH2 proteins. Right: overlapped height-profiles of ten proteins.

*Yoshitaka Saga, Kiyoshiro Kawano, Yuji Otsuka, Michie Imanishi, Yukihiro Kimura, Sayaka Matsui & Hitoshi Asakawa
Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2
Nature, Scientific Reports, volume 9, Article number: 3636 (2019)
DOI: https://doi.org/10.1038/s41598-019-40082-y

Please follow this external link to read the full article: https://www.nature.com/articles/s41598-019-40082-y

Open Access The article “Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2” by Yoshitaka Saga, Kiyoshiro Kawano, Yuji Otsuka, Michie Imanishi, Yukihiro Kimura, Sayaka Matsui & Hitoshi Asakawa is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.