On Wireless BioSensors!

The last paper of T. Ruzgas, J. Sotres etal at Malmö University (Sweden) starts with a disturbing statement: “It is predicted that with the development of Internet of Things technology by 2025 we expect more than 1000 connected devices per human”. With this idea in mind they are studying how to develop robust and cheap biosensors that will provide us with health information. And for that they are exploiting the ability of enzymes to “establish direct electron transfer contact with electrically conducting materials”.

 

This research, that made it to the cover of ChemElectroChem, is getting us closer to a cyborg-like healthier future.

DIPC 2018 Activity Report

One of our pictures was recently used to illustrate DIPC’s 2018 activity report. Lots of great friends there doing amazing research work!

On frogs, tadpoles and better batteries

My vast ignorance of chemistry doesn’t allow me to talk about this article, so here I leave you the abstract:

“Trapping negative charges in polymer electrolytes using a frog‐shaped, ether‐functionalized anion (EFA) is presented by H. Zhang, J. Carrasco, M. Armand, and co‐workers in their Communication on page 12070 ff. The bis(trifluoromethanesulfonyl)imide anion (TFSI), shown as a slippery tadpole, is highly mobile in poly(ethylene oxide) (PEO) matrix. In contrast, the ethylene oxide legs in EFA endow trapping interactions between the anion and PEO, which suppresses mobility”. [read more]

I did this picture on request and under close supervision of Dr. Heng Zang and Dr. Javier Carrasco (CIC Energigune, Spain). It deserved the inside cover of Angewandte Chemie (two in a row!).

 

Nature already did it!

Protein based electronics. I’ll say it again. Protein based electronics. Dr. Linda Zotty and Prof. Carlos Cuevas (IFIMAC, Spain) are working in something that stills looks like science fiction to me: protein-bioelectronics.

In particular they are studying how to turn a redox protein (Cytochrome C) into a viable switch. These proteins belong to a family of redox-active proteins that act as electron carriers in biological energy conversion systems (as in those involved in cellular respiration). Together with groups from the Weizmann Institute of Science (Israel) and Shemyakin-Ovchinnikov Institute of Bioorganic chemistry (Russia), they’ve theoretically shown how a Gold-Cytochrome-Gold structure can work as a voltage controlled switch.

Their research has been published in Angewandte Chemie and has been presented in the inside back cover.

 

A strain tunable single-layer MoS2 photodetector

Lets take a single layer of MoS2. Lets attach it to a surface in such a way that it can be stretched (or compressed) and there you have it: A strain tunable single-layer MoS2 photodetector. A device which uses strain to change the electrical and optical properties of 2D materials. In particular they’ve proven that with this method, they can reversibly change the photoresponsivity, the response time and the spectral bandwidth of single layered MoS2.

At Dr. Castellanos Lab, they are excelling at beautiful and elegant research. “… we demonstrated that applying tensile biaxial strain to the MoS2 device can be an effective strategy to increase both the responsivity and the wavelength bandwidth of the photodetector (at the expense of a slower response time), while compressive strain can be exploited to yield faster photodetectors (although with a lower photoresponse and with a narrower wavelength bandwidth). This adaptable optoelectronic performance of this device can be very useful to adjust the photodetector operation to different lighting conditions, similarly to human eye adaptability (scotopic vision during the night vs. photopic vision during the daylight).

Their research is a collaboration between ICMM-CSIC, Imdea Nanociencia and the State Key Laboratory of Tribology, Tsinghua University, Beijing and has been recognized with the inner cover of Materials Today.

Swiss Army SPM

Mario Lanza proposes a new scanning probe microscopy technique that can examine local phenomena, and conductive atomic force microscopy, in particular, study local electromechanical properties. Check it in Nature Electronics!

In this schematic illustration we did to illustrate his proposition, it is shown how this setup, would allow multiple experiments to be carried out simultaneously and under vacuum conditions.

 

It comes in colors everywhere

A research group at IMDEA Nanociencia (together with the University of Grenoble and Berkeley) have presented a new switchable iron-based coordination polymer, which works as a reversible acetonitrile sensor.

Coordination polymers are emerging as molecular sensing materials for a variety of reasons: they are not toxic, environmentally friendly and above all, they’re highly responsive to a wide variety of external stimuli.

This polymer in particular, the unutterable {[Fe(H2O)2(CH3CN)2(pyrazine)](BF4)2·(CH3CN)2}, happens to be an excellent acetonitrile sensor: a toxic volatile organic compound, that makes its detection a major issue. The desorption of interstitial acetonitrile changes reversibly the color of the polymer together with its electronic and magneto–structural properties.

On request of José Sánchez Costa and Enrique Burzuri we made this picture, showing the reversibility of the process, that made it to the back cover of Chemical Science.

 

Magnetism and odd numbers

We’ve talked about Prof. Dr. Patrick Maletinsky’s research ([1], [2]) in several ocasions. His research group is excelling at the development of new microscopies. Recently they’ve pushed the envelope another step further by for the first time “measuring the magnetic properties of atomically thin van der Waals materials on the nanoscale”. 2D materials are going to play a key role in the next technological revolution. And the we need tools to study and characterize these systems.

Quantum Sensing Lab together with several groups at the university of Geneva, have determined the magnetic properties of single atomic layers of chromium triiodide (CrI3).

By carefully doing this, they’ve found that the magnetic properties of this material depends on the number of layers of CrI3: an even number of layers produces no magnetic fields while an odd number of them, produces the same fields as a single CrI3 layers. This results have been published in Science.

We made this picture to illustrate this amazing step forward with the help of Patrick Maletinsky and Lucas Thiel. [Read more at UniBas]

Let there be light!

A research team at TU Wien ( Matthias Paur, Aday J. Molina-Mendoza, et al. ) together with groups from Germany and Japan, have developed a new type of light-emitting diode. What’s exciting about it? That it produces light from the decay of an exciton. An exciton is a bound state of an electron and an electron hole which orbit around one another. This electron-hole pairs can be created by applying electrical charges and when these pairs recombine, they produce energy in the form of light.

To make it even more exotic, they’ve created this diode by producing excitons in two dimensional materials. This systems have shown to be not only a great way to study this quasiparticles but also have a great potential to became a usable device. Just to name one of its characteristics, the wavelength of the light emitted by this devices is highly tunable.

With the supervision of Aday Molina-Mendoza, we did this picture to illustrate the emission process. This research has been published in Nature Communications.