Thermochromic Color Switching to Temperature Controlled Volatile Memory and Counter Operations with Metal–Organic Complexes and Hybrid Gels

Abstract

Temperature is often not considered as ap recision stimulus for artificial chemical systems in contrast to the hostguest interactions related to many natural processes.Similarly, mimicking multi-state volatile memory operations using asingle molecular system with temperature as aprecision stimulus is highly laborious.H ere we demonstrate howamixture of iron(II) chloride and bipyridine can be used as ar eversible color-to-colorless thermochromic switch and logic operators. The generality of the approach was illustrated using Co II and Ni II salts that resulted in color-to-color transitions.DMSO gels of these systems,e xhibited reversible opaque-transparency switching. More importantly,o ptically readable multi-state volatile memory with temperature as aprecision input has been demonstrated. The stored data is volatile and is lost instantaneously upon withdrawal or changeo ft emperature.S imultaneous read-out at multiple wavelengths results in single-input/ multi-output sequential logic operations such as data accumulators (counters) leading to volatile memory states.The present system provides access to thermoresponsive materials wherein temperature can be used as aprecision stimulus.

Switchable Supramolecular Configurations of Al3+/LysTPY Coordination Polymers in a Hydrogel Network Controlled by Ultrasound and Heat

“…Very recently, Ajayaghosh and coworkers have presented thermally labile metallogels in dimethyl sulfoxide (DMSO) based on ligand exchange reactions, which could be utilized for multi-state volatile memory and counter operations. 17 Thermal control of reversible host−guest interaction has also been realized in coordination polymers. 18 So far, however, supplying a method of control on the coordination interactions in hydrogels that is reversible, instant, and remote, while also being green with nonchemical stimuli, remains a challenge.…”

Bionic Thermosensation Inspired Temperature Gradient Sensor Based on Covalent Organic Framework Nanofluidic Membrane with Ultrahigh Sensitivity

“…Respective sensors are ubiquitous in daily life and in almost all industrial processes. It is estimated that temperature sensors occupy ~80% of the worldwide sensor market [4][5][6] . The physicochemical underpinnings of the current thermal sensation systems include (1) thermometers based on the thermal expansion of the filled liquids, (2) optical sensors based on thermochromic color switching, and (3) thermocouples based on the Seebeck effect.…”

“…The xintercepts ( ) of the current-voltage (I-V) plots exhibited average reversal potentials (tree times) of -58.4 mV, -112 4. mV, and -109.6 mV for cis/trans = 1.0 mM/0.1 mM, 10 mM/0.1 mM, and 100 mM/0.1 mM KCl, respectively (Figure3b).The permeability ratios of K + /Cl − calculated based on the Goldman equation (equation 1) were 449, 416, and 78, respectively, confirming the preferential passage of cations over a wide range of concentration gradients 57 .To gain additional insight into the ion transport profiles inside the nanopores, theoretical calculations using a continuum approach based on the Nernst-Planck-Poisson equations were performed using COMSOL.…”

Blue-emissive two-component supergelator with aggregation-induced enhanced emission

“…The study of fluorescent supramolecular gels derived from the self-assembly of low molecular weight organogelators has received considerable attention in recent years due to their numerous applications as soft emissive materials in nanoscience and nanotechnology. 1 Supramolecular gels are typically composed of three dimensional (3D) entangled network of the gelator molecules assembled via various non-covalent interactions such as hydrogen bonding, 2 π–π stacking, 3 donor–acceptor 4 and hydrophobic interactions. 5 Depending upon the chemical structure and functionality tethered on the gelator, various superstructures are possible for the self-assembled nanostructures such as vesicles, 6 nanofibers, 7 micelles 8 and helical structures.…”