Cover Page June-2019-Advanced Materials Letters

Advanced Materials Letters

Volume 10, Issue 6, Pages 391-394, June 2019
About Cover

The cover photo describes the graphical representation of a programmable microfluidic device for the capture and detection of a variety of cells and bacteria. Recently, the interest in microfluidic technology has progressed considerably since the last decade due to its advanced applications in many areas including protein biochemistry, cell culture, detection, and electromechanical systems.


Visualization of mechanical loads with semiconductor nanocrystals 

Martin Moebius1, Joerg Martin2*, Melinda Hartwig1, Ricardo Decker1, Lothar Kroll1, 3, Reinhard R. Baumann1, 2, Thomas Otto1, 2 

1Technische Universität Chemnitz, Chemnitz, 09126, Germany

2Fraunhofer Institute for Electronic Nano Systems, Chemnitz, 09126, Germany

3Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz, 09126, Germany

Adv. Mater. Lett., 2019, 10 (6), pp 391-394

DOI: 10.5185/amlett.2019.2221

Publication Date (Web): Jan 14, 2019

E-mail: joerg.martin@enas.fraunhofer.de

Abstract

Fibre-reinforced plastics offer excellent mechanical properties at low weight. Hence, such materials are ideally suited to reduce energy consumption and CO2 emission, e.g. in aircraft and automotive engineering, shipbuilding or in the field of renewable energies. However, in contrast to e.g. metals, lightweight structures are sensitive to mechanical loads exceeding a certain approved range. In order to detect mechanical overloads at an early stage and to avoid consequential failures in lightweight structures, we recently proposed a novel concept of a thin-film sensor for visualization of mechanical loads by using photoluminescence quenching of quantum dots. Here, we present results according to the optimization of the ionization efficiency of the cadmium selenide quantum dots by using poly(N-vinylkarbazol)(PVK) as charge transport material with favorable energy levels. Measurements of the photoluminescence intensity and electrical power confirm an increase of efficiency with almost the same photoluminescence drop compared to N,N,N′,N′-Tetrakis(3-methylphenyl)-3,3′-dimethyl-benzidine (HMTPD), most likely by the higher valence band offset between quantum dots and PVK. Furthermore, an integration of a layer stack with connected ceramic piezoelectric transducer demonstrates the successful use of the sensor system for mechanical load detection in lightweight structures. 

Keywords

Structural health monitoring, lightweight structures, photoluminescence, quantum dots.

Previous issues

Artificial intelligence and machine learning empowering the mass medicine

Piezo-therapy in cancer: Current research and perspectives

Magnetic microwires for sensor applications

A fundamental study on the mechanistic impact of repeated de- and rehydration of Ca(OH)2 on thermochemical cycling in technical scale

Fabrication and characterization of nano-bridge Josephson junction based on Fe0.94Te0.45Se0.55 thin film

Riboflavin-UVA gelatin crosslinking: Design of a biocompatible and thermo-responsive biomaterial with enhanced mechanical properties for tissue engineering

Broadband and fast photodetectors based on multilayer p-MoTe2/n-WS2 heterojunction with graphene electrodes

Ionic liquid [BMIM][Cl] immobilized on cellulose fibers from pineapple leaves for desulphurization of fuels

Synthesis and role of co-dopants (alkaline earth divalents and halides) on the photoluminescence of Eu2+ doped BaAl2O4 phosphor

Metal oxide (V2O5) incorporated fly ash based geopolymer for better sustainable engineering composites

Highly efficient storage of solar gains using aluminum foam heat exchangers  

Green fabrication of zinc oxide nanospheres by aspidopterys cordata for effective antioxidant and antibacterial activity

Effect of diamantane on the thermal stability of cryomilled aluminum alloy

Upcoming Congress

Knowledge Experience at Sea TM