Showing posts with label mofs. Show all posts
Showing posts with label mofs. Show all posts

Thursday, May 4, 2023

MOF-Mania


Nothing says synthetic biology, artificial life, or humanoid biobots like metal-organic frameworks (MOFs). It's in the name. 


Designing the perfect membrane for clean separation of gases
Jun 2022, phys.org

MMOF - mixed-matrix metal-organic framework (MOF nanosheets in a polymer matrix)

via King Abdullah University of Science and Technology: Shuvo Jit Datta et al, Rational design of mixed-matrix metal-organic framework membranes for molecular separations, Science (2022). DOI: 10.1126/science.abe0192. www.science.org/doi/10.1126/science.abe0192




Researchers use biomolecule-loaded metal-organic frameworks nanopatterns to aid artificial stem cell differentiation
Jun 2022, phys.org

MOFs, or metal organic frameworks, are hybrid crystalline porous materials constructed using metal ions and organic ligands. Due to their porous nature, MOFs are excellent for trapping and releasing molecules of interest over a long period of time. This gave the team the idea to use MOFs for storing and releasing from nanopit arrays biocompatible nanoparticles necessary for stem cell differentiation.

via Chung-Ang University, Republic of Korea: Yeon-Woo Cho et al, Single metal-organic framework–embedded nanopit arrays: A new way to control neural stem cell differentiation, Science Advances (2022). DOI: 10.1126/sciadv.abj7736


GTUB3 is the first microporous, metal-organic solid that is both conductive and photoluminescent
Dec 2022, phys.org

The problem to date is that the majority of MOFs are very poor conductors of electricity. The new material created by the researchers, called GTUB3, is both a good conductor as well as chemically and thermally extremely stable. What makes it unique is that it is also photoluminescent, meaning that it glows when irradiated with light. As a result, it could also be used in optoelectronic applications and solar cells.

via Technical University of Berlin: Yunus Zorlu et al, Electrically Conductive Photoluminescent Porphyrin Phosphonate Metal–Organic Frameworks, Advanced Optical Materials (2022). DOI: 10.1002/adom.202200213


New AI model transforms understanding of metal-organic frameworks
Mar 2023, phys.org

"We pre-trained the MOFTransformer with a million hypothetical MOFs to learn their essential characteristics, which we represented as a sentence. The model was then trained to complete these sentences to give the MOF's correct characteristics."

via Ecole Polytechnique Federale de Lausanne and KAIST: Jihan Kim, A multi-modal pre-training transformer for universal transfer learning in metal–organic frameworks, Nature Machine Intelligence (2023). DOI: 10.1038/s42256-023-00628-2.


Thursday, September 22, 2022

The Weird Computer Revolution


Materials science is moving beyond the "perimeter of ignorance" faster than we can keep up with it. And definitely faster than architects, civil engineers, industrial designers, etc. can keep up with it. Materials scientists, and even computer scientists in overlapping fields, are finding lots of "completely unexpected" things that defy our understanding of how matter behaves. 

Combine that with the "weird computer" revolution that happens when the matter itself becomes programmable, and the future gets hard to imagine. (Maybe less hard to imagine is the resulting human health and ecological disasters that will happen, kind of like how the industrial revolution created climate change).

A world where every molecule is itself a computer - The farthest I can get when thinking about this is Stanislav Lem's Solaris (1961) where the planet itself was not only alive but conscious, and trying to communicate with humans.



Shape-shifting worm blob model could inspire future robot swarms
Oct 2021, phys.org

'Entangled active matter collectives' are a hot topic in robotics and materials science...

via Georgia Tech: Chantal Nguyen et al, Emergent Collective Locomotion in an Active Polymer Model of Entangled Worm Blobs, Frontiers in Physics (2021). DOI: 10.3389/fphy.2021.734499


Physicists make square droplets and liquid lattices
Sep 2021, phys.org

Completely unexpected:

In their work, the team used combinations of oils with different dielectric constants and conductivities, then subjected the liquids to an electric field.

As well as being disrupted by the electric field, the liquids were confined into a thin, nearly two-dimensional sheet. This combination led to the oils reshaping into various completely unexpected droplets and patterns.

The droplets in the experiment could be made into squares and hexagons with straight sides, which is almost impossible in nature, where small bubbles and droplets tend to form spheres. The two liquids could be also made to form into interconnected lattices: grid patterns that occur regularly in solid materials but are unheard of in liquid mixtures. 

via Aalto University Department of Applied Physics in the Active Matter: Diversity of non-equilibrium patterns and emergence of activity in confined electrohydrodynamically driven liquids, Science Advances (2021). DOI: 10.1126/sciadv.abh1642


The next generation of robots will be shape-shifters
Mar 2022, phys.org

It is hoped that active matter will lead to a new generation of machines whose function will come from the bottom up. So, instead of being governed by a central controller (the way today's robotic arms are controlled in factories), these new machines would be made from many individual active units that cooperate to determine the machine's movement and function. This is akin to the workings of our own biological tissues, such as the fibers in heart muscle.

via University of Bath: Jack Binysh et al, Active elastocapillarity in soft solids with negative surface tension, Science Advances (2022). DOI: 10.1126/sciadv.abk3079


Self-sensing artificial muscle based on liquid crystal elastomer and low-melting point alloys
May 2022, phys.org

Inspired by the coupled behavior of muscles, bones, and nerve systems of mammals and other living organisms to create a multifunctional artificial muscle in the lab.

via Frontier Institute of Science and Technology, Jiaotong University, China: Haoran Liu et al, Shape-programmable, deformation-locking, and self-sensing artificial muscle based on liquid crystal elastomer and low–melting point alloy, Science Advances (2022). DOI: 10.1126/sciadv.abn5722


Ancient art of kirigami meets AI for better materials design
Apr 2022. phys.org

via Argonne National Laboratory: Pankaj Rajak et al, Autonomous reinforcement learning agent for stretchable kirigami design of 2D materials, npj Computational Materials (2021). DOI: 10.1038/s41524-021-00572-y

And: Pankaj Rajak et al, Autonomous reinforcement learning agent for chemical vapor deposition synthesis of quantum materials, npj Computational Materials (2021). DOI: 10.1038/s41524-021-00535-3


A new approach to tackle optimization problems using Boltzmann machines
Apr 2022, phys.org

"Optimization problem" is codeword for 1. slime mold computers, 2. quantum computers, and 3. weird computers in general, like crystals, dust, liquid photons, BECs, you name it, and because the optimization problem, also known as the traveling salesman problem, and which is related to random walks, or the drunkard's walk, is a type of problem that classical computers are really bad at, but quantum computers, slime mold, etc are really good at. 

Restricted Boltzmann machines (RBMs) are generative neural networks. They speak the language of big data and show you the patterns in it. 

RBMs rely on binary activations, circumventing the direct matrix-vector multiplications that are typically the most computationally demanding for deep learning networks. 

"Our algorithm functions by using the basic principles of digital logic in a new way," Patel explained. "Usually, digital gates only function in the forward direction, but by using probabilistic graphical models and machine learning, we have shown ways of operating them in reverse
Using this principle, we design our probabilistic digital circuits in a way that can solve the forward problem ("Is this set of inputs a valid solution?" or "What is 191 x 223?"), but because the system is reversible, it can also answer the much harder reverse problem ("What are all the sets of inputs that produce a valid solution?" and "What are A and B such that A x B = 42593?" )."

via University of California Berkeley: Saavan Patel et al, Logically synthesized and hardware-accelerated restricted Boltzmann machines for combinatorial optimization and integer factorization, Nature Electronics (2022). DOI: 10.1038/s41928-022-00714-0


A new age of 2.5D materials
May 2022, phys.org

Scientists are exploring new ways to artificially stack two-dimensional (2D) materials, introducing so-called 2.5D materials with unique physical properties. 

They're made using chemical vapor deposition, and they're made out of graphene, hexagonal boron nitride, and transition metal dichalcogenides.

via Kyushu University: Hiroki Ago et al, Science of 2.5 dimensional materials: paradigm shift of materials science toward future social innovation, Science and Technology of Advanced Materials (2022). DOI: 10.1080/14686996.2022.2062576


Mathematicians suggest liquid crystals could be used to create building blocks for a new kind of computer
Aug 2022, phys.org

The orientations of LCD molecules could be manipulated using an electric field and perform calculations similar to the way they are done with standard logic gates. The researchers note that, in their approach, calculations would appear as ripples moving through the crystal.

via MIT: Žiga Kos et al, Nematic bits and universal logic gates, Science Advances (2022). DOI: 10.1126/sciadv.abp8371


New programmable materials can sense their own movements
Aug 2022, phys.org

"Sensorizing structures"

Method for 3D printing materials with tunable mechanical properties from incorporated networks of air-filled channels, and which can sense how they are moving and interacting with the environment. 

Also "architected materials" have customizable mechanical properties based solely on its geometry.

via MIT: Fluidic innervation sensorizes structures from a single build material, Science Advances (2022). science.org/doi/10.1126/sciadv.abq4385


Researchers engineer novel material capable of 'thinking'
Aug 2022, phys.org

"We discovered how to use mathematics and kinematics in mechanical-electrical networks." 

The researchers were stuck, until they rediscovered a 1938 paper published by Claude E. Shannon, who described a way to create an integrated circuit by constructing mechanical-electrical switching networks that follow the laws of Boolean mathematics.

The material is made from conductive and non-conductive rubber materials that sense and react to how forces are applied to them.

via Pennsylvania State University: Ryan Harne, Mechanical integrated circuit materials, Nature (2022). DOI: 10.1038/s41586-022-05004-5.

Tuesday, March 29, 2022

I Am the Robot Now


AKA Human Skin Is a Conductible Material
Image credit: Peepo, iStock, 2021

The amount of research being done in the field of wearables and ambient energy harvesting is staggering.


A novel approach to wirelessly power wearable devices
Jun 2021, phys.org

It's like a microscope for energy -- all of the sudden, the "waste energy" from our appliances and devices, in electromagnetic form, is powering tiny ubiquitous smart particles all around us.

Their technology enables a single device, such as a mobile phone placed in the pocket, to wirelessly power other wearable devices on a user's body, using the human body as a medium for power transmission.

A user just needs to place the transmitter on a single power source, such as the smart watch on a user's wrist, while multiple receivers can be placed anywhere on the person's body. The system then harnesses energy from the source to power multiple wearables on the user's body via a process termed as body-coupled power transmission. In this way, the user will only need to charge one device, and the rest of the gadgets that are worn can simultaneously be powered up from that single source. The team's experiments showed that their system allows a single power source that is fully charged to power up to 10 wearable devices on the body, for a duration of over 10 hours.
As a complementary source of power, the NUS team also looked into harvesting energy from the environment. Their research found that typical office and home environments have parasitic electromagnetic (EM) waves that people are exposed to all the time, for instance, from a running laptop. The team's novel receiver scavenges the EM waves from the ambient environment, and through a process referred to as body-coupled powering, the human body is able to harvest this energy to power the wearable devices, regardless of their locations around the body.

via National University of Singapore: Jiamin Li et al, Body-coupled power transmission and energy harvesting, Nature Electronics (2021). DOI: 10.1038/s41928-021-00592-y


A new material made from carbon nanotubes can generate electricity by scavenging energy from its environment
Jun 2021, phys.org

Electrochemistry without wires. This is an organic solvent that generates a current via alcohol oxidation. The catch? The nanotubes are coated in "Teflon-like" material. Gonna have to fix that part (PFAS).

via Massachusetts Institute of Technology: Albert Tianxiang Liu et al, Solvent-induced electrochemistry at an electrically asymmetric carbon Janus particle, Nature Communications (2021). DOI: 10.1038/s41467-021-23038-7


Using starch and baking soda to harvest mechanical energy
Jun 2021, phys.org

via Daegu Gyeongbuk Institute of Science and Technology: Sugato Hajra et al, A Green Metal–Organic Framework‐Cyclodextrin MOF: A Novel Multifunctional Material Based Triboelectric Nanogenerator for Highly Efficient Mechanical Energy Harvesting, Advanced Functional Materials (2021). DOI: 10.1002/adfm.202101829


Skin in the game: Transformative approach uses the human body to recharge smartwatches
Jul 2021, phys.org

via University of Massachusetts Amherst: Noor Mohammed et al, ShaZam, Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies (2021). DOI: 10.1145/3463505


Conductive seams, when strategically placed in clothing, can accurately track body motion
Jul 2021, phys.org

via University of Bath: Olivia Ruston et al, More than it Seams: Garment Stitching in Wearable e-Textiles, Designing Interactive Systems Conference 2021 (2021). DOI: 10.1145/3461778.3462103


First-ever transient pacemaker harmlessly dissolves in body
Jul 2021, phys.org

via Northwestern University: Fully implantable and bioresorbable cardiac pacemakers without leads or batteries, Nature Biotechnology (2021). DOI: 10.1038/s41587-021-00948-x


Sweat-proof 'smart skin' takes reliable vitals, even during workouts and spicy meals
Jul 2021, phys.org

Writes itself now:

The patch is patterned with artificial sweat ducts, similar to pores in human skin, that the researchers etched through the material's ultrathin layers. The pores perforate the patch in a kirigami-like pattern, similar to that of the Japanese paper-cutting art. The design ensures that sweat can escape through the patch, preventing skin irritation and damage to embedded sensors.

via Massachusetts Institute of Technology: H. Yeon el al., "Long-term reliable physical health monitoring by sweat pore–inspired perforated electronic skins," Science Advances (2021). DOI: 10.1126/sciadv.abg8459


Microfiber-based metafabric provides daytime radiative cooling
Jul 2021, phys.org

Sooner than we think, we will be wearing today's equivalent of a space suit in order to go outside, on Earth:

The final design added titanium dioxide powder to polymer fibers to make them reflective, and adding polylactic acid to allow the material to emit mid-infrared radiation. The researchers created a fabric using a weaving technique that allowed air to circulate. The researchers tested their material by using it to create a vest. One side of the vest was made of cotton, the other with the material they had developed. A volunteer wore the vest outside in the sun for an hour. Measurements of his skin temperature showed it to be almost 5 degrees Celsius cooler on the new material side. The researchers also note that in addition to reducing heat, clothes made of their material would be biodegradable.

via: Shaoning Zeng et al, Hierarchical-morphology metafabric for scalable passive daytime radiative cooling, Science (2021). DOI: 10.1126/science.abi5484


New chemistry enables using existing technology to print stretchable, bendable circuits on artificial skin
Jul 2021, phys.org

In a new study, the group describes how they have printed stretchable-yet-durable integrated circuits on rubbery, skin-like materials, using the same equipment designed to make solid silicon chips — an accomplishment that could ease the transition to commercialization by switching foundries that today make rigid circuits to producing stretchable ones.

via Stanford University: Yu-Qing Zheng et al, Monolithic optical microlithography of high-density elastic circuits, Science (2021). DOI: 10.1126/science.abh3551

Nanoscopic Schematic by Ella Maru Studio

New nanotech will enable a 'healthy' electric current production inside the human body
Jul 2021, phys.org

For example, a device made from this material may replace a battery that supplies energy to implants like pacemakers, though it should be replaced from time to time. Body movements—like heartbeats, jaw movements, bowel movements, or any other movement that occurs in the body on a regular basis—will charge the device with electricity, which will continuously activate the implant."

via Tel-Aviv University: Santu Bera et al, Molecular engineering of piezoelectricity in collagen-mimicking peptide assemblies, Nature Communications (2021). DOI: 10.1038/s41467-021-22895-6


Detecting an unprecedented range of potentially harmful airborne compounds
Aug 2021, phys.org

Usually, if you want to sample for VOCs, you first have to know which VOC you're looking for. You think there's some diacetyl exposure? Then you dose your sampler with a chemical that latches onto diacetyl. But what if we don't know? You're in luck! This new approach uses nanopores of silica; they are so small that they use van der Waals forces, typically really weak forces, to capture any VOCs that float by. Then they can heat up the sensor and re-volatalize whatever got trapped there, and sniff it through a GCMS.

via American Chemical Society: Nanoporous materials for measuring environmental VOC exposures, ACS Fall 2021.


Indoor lighting creates power for rechargeable devices, sensors
Aug 2021, phys.org

Since there is usually plenty of indoor ambient light from different sources, a ceiling light in an office environment would be enough to charge any of the mini modules that were tested, making them all viable as power sources for indoor batteries and sensors.

via American Institute of Physics: https://horizons.aip.org/energystorage-conversion/


Revolutionary Self-Aware Materials Build the Foundation for Living Structures
Oct 2021, scitechdaily.com

A metamaterial system that acts as its own sensor, recording and relaying important information about the pressure and stresses on its structure, fusing advanced metamaterial and energy harvesting technologies at multiscale. With built-in triboelectric nanogenerator mechanism; a smart-stint that monitors bloodflow and restricts vessel size accordingly, or just a smart-bridge that can communicate areas of weakness by sensing pressure.

As I write this, it sounds to me like the bridge can be conscious, because it can feel. So in the distant future, we won't be able to just knock down a house, because it will have feelings. Design for Dissassembly then, maybe?

via University of Pittsburg's Intelligent Structural Monitoring and Response Testing (iSMaRT) Lab: “Multifunctional meta-tribomaterial nanogenerators for energy harvesting and active sensing” by Kaveh Barri, Pengcheng Jiao, Qianyun Zhang, Jun Chen, Zhong Lin Wang and Amir H. Alavi, 16 April 2021, Nano Energy. DOI: 10.1016/j.nanoen.2021.106074


Engineers develop process that turns ordinary clothing into biosensors
Nov 2021, phys.org

Gold and silver nanocomposite-based biostable and biocompatible electronic textile for wearable electromyographic biosensors.

via University of Utah: Taehwan Lim et al, Gold and silver nanocomposite-based biostable and biocompatible electronic textile for wearable electromyographic biosensors, APL Materials (2021). DOI: 10.1063/5.0058617


Form fit: Device wraps around hot surfaces, turns wasted heat to electricity
Jan 2022, phys.org

via Pennsylvania State University: Wenjie Li et al, Conformal High-Power-Density Half-Heusler Thermoelectric Modules: A Pathway toward Practical Power Generators, ACS Applied Materials & Interfaces (2021). DOI: 10.1021/acsami.1c16117


Monday, July 26, 2021

Meta-Materials Mega-Thread

The phrase "metallic-organic framework" (MOF) has been appearing in headlines with more frequency, seemingly out of nowhere. Then again, when the material science revolution is fully underway, we will also wonder where the heck it came from. 

MOFs fall into the same general category as meta-materials, related to nano-this and graphene-that. These articles are a reminder that we're in for a whole new world. Kind of like what plastic did for the post-war world we live in today, or the synthetic chemical revolution of the late 1800's that gave our world "colors". 

Image credit: Metal Organic Framework by Mike Gipple at NETL

Programmable synthetic materials
Aug 2020, phys.org
In the future, MOFs could form the basis of programmable chemical molecules: for instance, an MOF could be programmed to introduce an active pharmaceutical ingredient into the body to target infected cells and then break down the active ingredient into harmless substances once it is no longer needed. Or MOFs could be programmed to release different drugs at different times.

via University of California Berkeley: Sequencing of metals in multivariate metal-organic frameworks, Science (2020). DOI: 10.1126/science.aaz4304 
Breakthrough technology purifies water using the power of sunlight
Aug 2020, phys.org
Metal-organic frameworks are a class of compounds consisting of metal ions that form a crystalline material with the largest surface area of any material known. In fact, MOFs are so porous that they can fit the entire surface of a football field in a teaspoon.

via Monash University: A sunlight-responsive metal–organic framework system for sustainable water desalination, Nature Sustainability (2020). DOI: 10.1038/s41893-020-0590-x
Study shows promising material can store solar energy for months or years
Dec 2020, phys.org
In tests, the researchers exposed the material to UV light, which causes the azobenzene molecules to change shape to a strained configuration inside the MOF pores. This process stores the energy in a similar way to the potential energy of a bent spring. Importantly, the narrow MOF pores trap the azobenzene molecules in their strained shape, meaning that the potential energy can be stored for long periods of time at room temperature.

The energy is released again when external heat is applied as a trigger to 'switch' its state, and this release can be very quick—a bit like a spring snapping back straight. This provides a heat boost which could be used to warm other materials of devices.

Further tests showed the material was able to store the energy for at least four months. This is an exciting aspect of the discovery as many light-responsive materials switch back within hours or a few days. The long duration of the stored energy opens up possibilities for cross-seasonal storage.

via by Lancaster University: Kieran Griffiths et al, Long-Term Solar Energy Storage under Ambient Conditions in a MOF-Based Solid–Solid Phase-Change Material, Chemistry of Materials (2020). DOI: 10.1021/acs.chemmater.0c02708
Physicists create tunable superconductivity in twisted graphene 'nanosandwich'
Feb 2021, phys.org

Come on with that name though.

via Massachusetts Institute of Technology: Tunable strongly coupled superconductivity in magic-angle twisted trilayer graphene, Nature (2021). DOI: 10.1038/s41586-021-03192-0

Flash graphene rocks strategy for plastic waste
Oct 2020, phys.org
It's called flashing -- expose plastic waste to eight seconds of high-intensity alternating current, followed by the DC jolt. You'll get turbostratic graphene. Yes, graphene from garbage. $125 of electricity turns a ton of plastic into a ton of graphene.
via Rice University: Wala A. Algozeeb et al, Flash Graphene from Plastic Waste, ACS Nano (2020). DOI: 10.1021/acsnano.0c06328
Researchers use origami to solve space travel challenge
Dec 2020, phys.org

Origami bellow-bag fuel storage containers.

via Washington State University: Kjell Westra et al, Compliant Polymer Origami Bellows in Cryogenics, Cryogenics (2020). DOI: 10.1016/j.cryogenics.2020.103226

DNA origami enables fabricating superconducting nanowires
Jan 2021, phys.org
 
via the American Institute of Physics: "DNA origami-based superconducting nanowires" AIP Advances, aip.scitation.org/doi/10.1063/5.0029781

Researchers turn coal powder into graphite in microwave oven
Jan 2021, phys.org
Using copper foil, glass containers and a conventional household microwave oven, University of Wyoming researchers have demonstrated that pulverized coal powder can be converted into higher-value nano-graphite.

"By cutting the copper foil into a fork shape, the sparks were induced by the microwave radiation, generating an extremely high temperature of more than 1,800 degrees Fahrenheit within a few seconds," says Masi, lead author of the paper. "This is why you shouldn't place a metal fork inside a microwave oven."

via University of Wyoming: Christoffer A. Masi et al, Converting raw coal powder into polycrystalline nano-graphite by metal-assisted microwave treatment. Nano-Structures & Nano-Objects Volume 25, 2021, 100660, ISSN 2352-507X, doi.org/10.1016/j.nanoso.2020.100660
'Magnetic graphene' forms a new kind of magnetism
Feb 2021, phys.org

via University of Cambridge: Matthew J. Coak et al. 'Emergent Magnetic Phases in Pressure-Tuned van der Waals Antiferromagnet FePS3.' Physical Review X (2021). DOI: 10.1103/PhysRevX.11.011024

A new way to make wood transparent, stronger and lighter than glass
Feb 2021, phys.org
The conventional method for making wood transparent involves using chemicals to remove the lignin—a process that takes a long time, produces a lot of liquid waste and results in weaker wood. In this new effort, the researchers have found a way to make wood transparent without having to remove the lignin.

The process involved changing the lignin rather than removing it. The researchers removed lignin molecules that are involved in producing wood color. First, they applied hydrogen peroxide to the wood surface and then exposed the treated wood to UV light (or natural sunlight). The wood was then soaked in ethanol to further clean it. Next, they filled in the pores with clear epoxy to make the wood smooth.

via University of Maryland: Qinqin Xia et al. Solar-assisted fabrication of large-scale, patternable transparent wood, Science Advances (2021). DOI: 10.1126/sciadv.abd7342
Japan developing wooden satellites to cut space junk
Dec 2020, BBC News