Symmetric flow cell cycling of a soluble phenothiazine.

Simple modification of N-ethylphenothiazine (left) with electron-donating substituents (right) increases the molecular charge-storage capacity of this donor.

A phenothiazine derivative with high solubility in carbonate solvents containing lithium salts showed extensive overcharge protection and, as a result, has been evaluated as a catholyte for non‐aqueous redox flow batteries. We report the testing of 3,7‐bis(trifluoromethyl)‐N‐ethylphenothiazine as a catholyte and 2,3,6‐trimethylquinoxaline as the anolyte in redox flow batteries containing 0.05, 0.15, and 0.35 M active material and found the longest capacity retention over about 60 cycles at 0.15 M. To our knowledge, this is the most soluble catholyte candidate with a robust radical cation.

Loosely aggregated conjugated polymer nanoparticles (CPNs) were used as nontoxic and efficient small interfering RNA (siRNA) delivery vehicles with delivery visualization. A significant down regulation (94%) of a target gene was achieved by transfection of HeLa cells with the CPNs/siRNA complexes, supporting CPN as a promising siRNA delivery carrier.

We report a solvent-free dry powder coating process for making LiNi 1/3 Mn 1/3 Co 1/3 O 2 (NMC) positive electrodes in lithium-ion batteries. This process eliminates volatile organic compound emission and reduces thermal curing time from hours to minutes. A mixture of NMC, carbon black, and poly(vinylidene difluoride) was electrostatically sprayed onto an aluminum current collector, forming a uniformly distributed electrode with controllable thickness and porosity. Charge/discharge cycling of the dry-powder-coated electrodes in lithium-ion half cells yielded a discharge specific capacity of 155 mAh g -1 and capacity retention of 80% for more than 300 cycles when the electrodes were tested between 3.0 and 4.3 V at arate of C/5. The long-term cycling performance and durability of dry-powder coated electrodes are similar to those made bythe conventional wet slurry-based method.This solvent-free dry powder coating process is a potentially lower-cost, higher-throughput, and more environmentally friendly manufacturing process compared with the conventional wet slurry-based electrode manufacturing method.