Direct Electrodeposition of Electrically Conducting Ni3(HITP)2 MOF Nanostructures for Micro-Supercapacitor Integration.

Micro-supercapacitors emerge as an important electrical energy storage technology expected to play a critical role in the large-scale deployment of autonomous microdevices for health, sensing, monitoring, and other IoT applications. Electrochemical double-layer capacitive storage requires a combination of high surface area and high electronic conductivity, with these being attained only in porous or nanostructured carbons, and recently found also in conducting metal-organic frameworks (MOFs). However, techniques for conformal deposition at micro- and nanoscale of these materials are complex, costly, and hard to upscale. Herein, the study reports direct, one step non-sacrificial anodic electrochemical deposition of Ni3(2,3,6,7,10,11-hexaiminotriphenylene)2 - Ni3(HITP)2, a porous and electrically conducting MOF. Employing this strategy enables the growth of Ni3(HITP)2 films on a variety of 2D substrates as well as on 3D nanostructured substrates to form Ni3(HITP)2 nanotubes and Pt@ Ni3(HITP)2 core-shell nanowires. Based on the optimal electrodeposition protocols, Ni3(HITP)2 films interdigitated micro-supercapacitors are fabricated and tested as a proof of concept.

Revealing the reversible solid-state electrochemistry of lithium-containing conjugated oximates for organic batteries.

In the rising advent of organic Li-ion positive electrode materials with increased energy content, chemistries with high redox potential and intrinsic oxidation stability remain a challenge. Here, we report the solid-phase reversible electrochemistry of the oximate organic redox functionality. The disclosed oximate chemistries, including cyclic, acyclic, aliphatic, and tetra-functional stereotypes, uncover the complex interplay between the molecular structure and the electroactivity. Among the exotic features, the most appealing one is the reversible electrochemical polymerization accompanying the charge storage process in solid phase, through intermolecular azodioxy bond coupling. The best-performing oximate delivers a high reversible capacity of 350 mAh g-1 at an average potential of 3.0 versus Li+/Li0, attaining 1 kWh kg-1 specific energy content at the material level metric. This work ascertains a strong link between electrochemistry, organic chemistry, and battery science by emphasizing on how different phases, mechanisms, and performances can be accessed using a single chemical functionality.

Chameleon Multienvironment Nanoreactors.

Nanoreactors consisting of hydrophilic porous SiO2 shells and amphiphilic copolymer cores have been prepared, which can easily self-tune their hydrophilic/hydrophobic balance depending on the environment and exhibit chameleon-like behavior. The accordingly obtained nanoparticles show excellent colloidal stability in a variety of solvents with different polarity. Most importantly, thanks to the assistance of the nitroxide radicals attached to the amphiphilic copolymers, the synthesized nanoreactors show high catalytic activity for model reactions in both polar and nonpolar environments and, more particularly, realize a high selectivity for the products resulting from the oxidation of benzyl alcohol in toluene.

Validation of the boronate sensor ContPY1 as a specific probe for fluorescent detection of hydrogen peroxide in plants.

Studying the implication of hydrogen peroxide in biological processes in plants remains a challenge due to the current shortcomings of H2O2-responsive probes. The use of ContPY1, a new fluorescent probe, which is highly selective and sensitive for H2O2, was investigated. To validate the use of ContPY1 on plants, we have generated protocols employing cells suspensions and leaves, and measured specifically H2O2 production by plants using spectrofluorometry and microscopy.

Chiral properties of tetrathiatriarylmethyl spin probes.

We report that tetrathiatriarylmethyl (trityl) EPR probes are chiral molecules at room temperature, the two stereoisomers that differ in their helicity being configurationally stable enough to be separated and stored independently.