Journal of Materials Chemistry Blog

Researchers in Japan have developed a white light-emitting device (WLED) that works in outdoor lighting systems but avoids disrupting plant growth.

Outdoor lighting systems can disrupt natural plant growth © Shutterstock

Lighting systems across much of the world are currently based on WLEDs, and there have been many advances to reduce energy consumption without loss of brightness. This is great news for indoor lighting but problems arise when these WLED systems are used for outdoor lighting.

Interested? Read the full story at Chemistry World.

The original article can be read below:

Plant habitat-conscious white light-emitting devices: Dy3+-emission considerably reduces involvement in photosynthesis
Tomohiko Nakajima, Harumi Hanawa and Tetsuo Tsuchiya
J. Mater. Chem. C, 2015, Advance Article
DOI: 10.1039/C4TC02558J

The UK laboratory behind the pee-powered mobile phone has gone a wee bit further and turned recycled photocopier paper into microbial fuel cells that instigate radio transmissions when fed fresh urine.

The device could find use in remote locations

Microbial fuel cells (MFCs) use bacteria to generate electricity from waste fluids. However, they are hindered by expensive and toxic components, low power output and lengthy inoculation periods, with the mobile phone-charging MFCs requiring bulky and specialist materials. In contrast, the new paper-based MFCs from Jonathan Winfield, at the Bristol BioEnergy Centre, and co-workers are much smaller, lighter and cheaper.

Interested? Read the full story at Chemistry World.

The original article can be read below:

Urine-activated origami microbial fuel cells to signal proof of life
Jonathan Winfield, Lily D. Chambers, Jonathan Rossiter, John Greenman and Ioannis Ieropoulos
J. Mater. Chem. A, 2015, Advance Article
DOI: 10.1039/C5TA00687B

Scientists in Germany have successfully preserved delicate structural details in scarab beetles by using an ionic polymer to drive carbonisation. Due to their fossil-like and stable carbon structure, the specimens are anticipated to last for thousands of years.

The beetle starts off blue but turns brown when covered with the polymer coating

Jiayin Yuan, who led the study at the Max Planck Institute of Colloids and Interfaces, explains how his team discovered the technique: ‘In the past year we began to investigate interactions between poly(ionic liquid)s [PILs] and natural matrixes like cotton. Cotton coated with PIL and carbonised was thermally stable and its natural bio-matrix was preserved. For this reason, and motivated by an intrinsic curiosity typical of us scientists, we wanted to explore and push forward this effect to its limit.’

Interested? Read the full story at Chemistry World.

The original article can be read below:

Microstructure replication of complex biostructures via poly(ionic liquid)-assisted carbonization
Martina Ambrogi, Karoline Täuber, Markus Antonietti and Jiayin Yuan
J. Mater. Chem. A, 2015, 3, 5778-5782
DOI: 10.1039/C5TA00149H

US scientists have developed an adhesive tape that can help objects match the infrared reflectance of their surroundings and disguise them from being seen by infrared cameras. The flexible coating – based on a protein found in cephalopod skin – can moderate reflectance simply by stretching and may find application in military camouflage kit.

Cephalopods – such as squid, octopuses and cuttlefish – are nature’s masters of disguise. Their skins contain iridophores, cells that reflect and manipulate incident light to spectacular effect. Their plasma membranes fold to encompass lamellar-like platelets containing reflectin. Reversible phosphorylation of reflectin changes the size and structure of the lamellae, changing the iridophore’s reflectance across the visible spectrum.

Cuttlefish and other cephalopods are some of nature’s best camouflage artists © Shutterstock

 Interested? Read the full story at Chemistry World.

The original article can be read below:

Infrared invisibility stickers inspired by cephalopods
Long Phan, David D. Ordinario, Emil Karshalev, Ward G. Walkup IV, Michael A. Shenk and Alon A. Gorodetsky
J. Mater. Chem. C, 2015, Advance Article 
DOI: 10.1039/C5TC00125K

In a creative application of rational design, scientists in China have turned to nature to help overcome one of the key challenges facing the most probable successor to the lithium ion (Li-ion) battery. Lithium–sulfur (Li–S) batteries are cheaper, more sustainable and already capable of delivering up to three times the energy density of most Li-ion cells. However, they are held back by poor stability; a problem these researchers have confronted by functionalising the electrodes with DNA.

Li–S cells typically consist of a lithium metal anode and a carbon–sulfur cathode separated by a liquid electrolyte. Lithium ions dissolve from the anode during discharge, reacting with sulfur to form lithium polysulfides (Li₂S_x) at the cathode, while the reverse occurs on charging. Some of the polysulfide intermediates are unfortunately soluble in the electrolyte and their dissolution from the cathode leads to irreversible loss of the active sulfur, adversely affecting cell performance.

Interested? Read the full story at Chemistry World.

Functionalising electrodes with DNA significantly enhances performance © Shutterstock

The original article can be read below:

High-performance lithium/sulfur batteries by decorating CMK-3/S cathodes with DNA
Qiyang Li, Chenggang Zhou, Zhuan Ji, Bo Han, Liang Feng and Jinping Wu
J. Mater. Chem. A, 2015, Advance Article
DOI: 10.1039/C4TA06083K

Esca is a big problem for the wine industry © Shutterstock

A breathable and biodegradable adhesive patch to block fungal invasion of vine pruning wounds has been developed by nanotechnology scientists in the US.

Symptoms of fungal disease esca, or vine decline, include reduced yields, stunted growth and even the sudden death of vines. Esca is prevalent throughout the world and poses a significant threat to the wine industry – some countries have lost 40% of their grape harvest to the fungus. Often whole collections of vines have to be removed and replaced. No fungicide treatment is available – sodium arsenite was previously used for control in Europe, but is now banned for health reasons.

Interested? To read the full article, please visit Chemistry World.

The original article can be accessed below:

Biodegradable and Biocompatible Soy Protein/Polymer/Adhesive Sticky Nano-textured Interfacial Membranes for Prevention of Esca Fungi Invasion into Pruning Cuts and Wounds of Vines
Soumyadip Sett, Min Wook Lee, Martin Weith, B Pourdeyhimi and Alexander Yarin 
J. Mater. Chem. B, 2015, Accepted Manuscript
DOI: 10.1039/C4TB01887G

Inspired by both desert beetles and marine mussels, scientists in Saudi Arabia have devised a new method for creating micropatterned superhydrophobic surfaces that efficiently harvest fog.

The Namib Desert beetle survives by collecting moisture from the air

In semi-arid, desert regions, particularly in coastal areas where morning fog is abundant and rainfall is scarce, fog harvesting can be a crucial source of water. Indeed, the Namib Desert beetle is known to survive by collecting water from fog thanks to its unique back structure. An array of hydrophilic bumps across a waxy superhydrophobic surface collect then route droplets into the beetle’s mouth.

Interested? The full story can be read at Chemistry World.

The original article can be read below:

Inkjet printing for direct micropatterning of a superhydrophobic surface: toward biomimetic fog harvesting surfaces
Lianbin Zhang, Jinbo Wu, Mohamed Nejib Hedhili, Xiulin Yang and Peng Wan
J. Mater. Chem. A, 2015, Advance Article
DOI: 10.1039/C4TA05862C