Polyanthraquinone-Triazine-A Promising Anode Material for High-Energy Lithium-Ion Batteries.

A novel covalent organic framework polymer material that bears conjugated anthraquinone and triazine units in its skeleton has been prepared via a facile one-pot condensation reaction and employed as an anode material for Li-ion batteries. The conjugated units consist of C═N groups, C═O groups, and benzene groups, which enable a 17-electron redox reaction with Li per repeating unit and bring a theoretical specific capacity of 1450 mA h g-1. The polymer also shows a large specific surface area and a hierarchically porous structure to trigger interfacial Li storage and contribute to an additional capacity. The highly conductive conjugated polymer skeleton enables fast electron transport to facilitate the Li storage. In this way, the polymer electrode shows a large specific capacity and favorable cycling and rate performance, making it an appealing anode choice for the next-generation high-energy batteries.

Nitrogen-Doped Perovskite as a Bifunctional Cathode Catalyst for Rechargeable Lithium-Oxygen Batteries.

In this work, nitrogen-doped LaNiO3 perovskite was prepared and studied, for the first time, as a bifunctional electrocatalyst for oxygen cathode in a rechargeable lithium-oxygen battery. N doping was found to significantly increase the Ni3+ contents and oxygen vacancies on the bulk surface of the perovskite, which helped to promote the oxygen reduction reaction and oxygen evolution reaction of the cathode and, therefore, enabled reversible Li2O2 formation and decomposition on the cathode surface. As a result, the oxygen cathodes loaded with N-doped LaNiO3 catalyst showed an improved electrochemical performance in terms of discharge capacity and cycling stability to promise practical Li-O2 batteries.

The combination of a polymer-carbon composite electrode with a high-absorptivity ruthenium dye achieves an efficient dye-sensitized solar cell based on a thiolate-disulfide redox couple.

To overcome the intrinsic shortcomings of the traditional iodide-triiodide redox couple and pursue a further performance improvement, intense efforts have been made to exploit alternative redox shuttles in dye-sensitized solar cells (DSCs). Herein, we report an energetic and kinetic view of DSCs when the iodine electrolyte is substituted with its thiolate counterpart and identify that a conventional platinum counter electrode presents low catalytic activity for the thiolate electrolyte, featuring a high charge transfer resistance found at the platinized fluorine-doped tin oxide (FTO). We employ conductive carbon black with several polymers to fabricate highly active composite catalysts for thiolate regeneration. The use of a highly active conductive carbon black and polymerized 3,4-ethylenedioxythiophene composition as a counter electrode combined with a high-absorptivity ruthenium dye C106 sensitized titania film has generated a DSC with an organic thiolated electrolyte, exhibiting an overall power conversion efficiency of 7.6% under AM1.5G full sunlight.