A Dynamic Metal-Organic Radical Emission System.

Developing new organic radical emission systems and regulating their luminescence properties presents a significant challenge. Herein, we build dynamic and multi-emission band radical luminescence systems by co-assembling inorganic metal salts with carbonyl compounds in ionic liquids. After the assembling, dual-band, and excitation wavelength-dependent emission was observed upon light irradiation, one emission band originates from carbonyl radical after light irradiation, the other band from the ligand-metal charge transfer (LMCT) state, which benefits from the charge transfer from the radicals to the metal salts.

Rapidly Generated, Ultra-Stable, and Switchable Photoinduced Radicals: A Solid-State Photochromic Paradigm for Reusable Paper Light-Writing.

Although photochromic molecules have attracted widespread interest in various fields, solid-state photochromism remains a formidable challenge, owing to the substantial conformational constraints that hinder traditional molecular photoisomerization processes. Benefiting from the significant color change upon radical generation, chemical systems enabling a photoinduced radical (PIR) behavior through photoinduced electron transfer (PET) could be ideal candidates for solid-state photochromism within minimized need of conformational freedom. However, the transient nature of radicals causes a dilemma in this Scheme.

The Hydroxylated Carbon Nanotubes as the Hole Oxidation System in Electrocatalysis.

The hydroxylated carbon nanotubes (CNTs-OH), due to their propensity to trap electrons, are considered in many applications. Despite many case studies, the effect of the electronic structure of the CNT-OH electrode on its oxidation properties has not received in-depth analysis. In the present study, we used Fe(CN) and Ru(NH) as redox probes, which differ in charge.

Tuning the Emission of Bis-ethylenedioxythiophene-thiophenes upon Aggregation.

The ability of small lipophilic molecules to penetrate the blood-brain barrier through transmembrane diffusion has enabled researchers to explore new diagnostics and therapies for brain disorders. Until now, therapies targeting the brain have mainly relied on biochemical mechanisms, while electrical treatments such as deep brain stimulation often require invasive procedures. An alternative to implanting deep brain stimulation probes could involve administering small molecule precursors intravenously, capable of crossing the blood-brain barrier, and initiating the formation of conductive polymer networks in the brain through polymerization.

Straintronics in phosphorene via tensile vs shear strains and their combinations for manipulating the band gap.

We study the effects of the uniaxial tensile strain and shear deformation as well as their combinations on the electronic properties of single-layer black phosphorene. The evolutions of the strain-dependent band gap are obtained using the numerical calculations within the tight-binding (TB) model as well as the first-principles (DFT) simulations and compared with previous findings. The TB-model-based findings show that the band gap of the strain-free phosphorene agrees with the experimental value and linearly depends on both stretching and shearing: increases (decreases) as the stretching increases (decreases), whereas gradually decreases with increasing the shear.

Wireless optoelectronic devices for vagus nerve stimulation in mice.

Vagus nerve stimulation (VNS) is a promising approach for the treatment of a wide variety of debilitating conditions, including autoimmune diseases and intractable epilepsy. Much remains to be learned about the molecular mechanisms involved in vagus nerve regulation of organ function. Despite an abundance of well-characterized rodent models of common chronic diseases, currently available technologies are rarely suitable for the required long-term experiments in freely moving animals, particularly experimental mice.

Direct measurement of oxygen reduction reactions at neurostimulation electrodes.

. Electric stimulation delivered by implantable electrodes is a key component of neural engineering. While factors affecting long-term stability, safety, and biocompatibility are a topic of continuous investigation, a widely-accepted principle is that charge injection should be reversible, with no net electrochemical products forming.

Chronic electrical stimulation of peripheral nerves via deep-red light transduced by an implanted organic photocapacitor.

Implantable devices for the wireless modulation of neural tissue need to be designed for reliability, safety and reduced invasiveness. Here we report chronic electrical stimulation of the sciatic nerve in rats by an implanted organic electrolytic photocapacitor that transduces deep-red light into electrical signals. The photocapacitor relies on commercially available semiconducting non-toxic pigments and is integrated in a conformable 0.

Faradaic Pixels for Precise Hydrogen Peroxide Delivery to Control M-Type Voltage-Gated Potassium Channels.

H O plays a significant role in a range of physiological processes where it performs vital tasks in redox signaling. The sensitivity of many biological pathways to H O opens up a unique direction in the development of bioelectronics devices to control levels of reactive-oxygen species (ROS). Here a microfabricated ROS modulation device that relies on controlled faradaic reactions is presented.

UV-to-IR Absorption of Molecularly p-Doped Polythiophenes with Alkyl and Oligoether Side Chains: Experiment and Interpretation Based on Density Functional Theory.

The UV-to-IR transitions in p-doped poly(3-hexylthiophene) (P3HT) with alkyl side chains and polar polythiophene with tetraethylene glycol side chains are studied experimentally by means of the absorption spectroscopy and computationally using density functional theory (DFT) and tight-binding DFT. The evolution of electronic structure is calculated as the doping level is varied, while the roles of dopant ions, chain twisting, and π-π stacking are also considered, each of these having the effect of broadening the absorption peaks while not significantly changing their positions. The calculated spectra are found to be in good agreement with experimental spectra obtained for the polymers doped with a molybdenum dithiolene complex.

The intrinsic volumetric capacitance of conducting polymers: pseudo-capacitors or double-layer supercapacitors?

The capacitance of conducting polymers represents one of the most important material parameters that in many cases determines the device and material performances. Despite a vast number of experimental studies, the theoretical understanding of the origin of the capacitance in conducting polymers remains unsatisfactory and appears even controversial. Here, we present a theoretical method, based on first principle capacitance calculations using density functional theory (DFT), and apply it to calculate the volumetric capacitance of two archetypical conducting polymers: poly(3,4-ethylene dioxythiophene) (PEDOT) and polypyrrole (PPy).