Cation-Induced Interfacial Hydrophobic Microenvironment Promotes the C-C Coupling in Electrochemical CO2 Reduction.

The electrochemical carbon dioxide reduction reaction (CO2RR) toward C2 products is a promising way for the clean energy economy. Modulating the structure of the electric double layer (EDL), especially the interfacial water and cation type, is a useful strategy to promote C-C coupling, but atomic understanding lags far behind the experimental observations. Herein, we investigate the combined effect of interfacial water and alkali metal cations on the C-C coupling at the Cu(100) electrode/electrolyte interface using ab initio molecular dynamics (AIMD) simulations with a constrained MD and slow-growth approach. We observe a linear correlation between the water-adsorbate stabilization effect, which manifests as hydrogen bonds, and the corresponding alleviation in the C-C coupling free energy. The role of a larger cation, compared to a smaller cation (e.g., K+ vs Li+), lies in its ability to approach the interface through desolvation and coordinates with the *CO+*CO moiety, partially substituting the hydrogen-bonding stabilizing effect of interfacial water. Although this only results in a marginal reduction of the energy barrier for C-C coupling, it creates a local hydrophobic environment with a scarcity of hydrogen bonds owing to its great ionic radius, impeding the hydrogen of surrounding interfacial water to approach the oxygen of the adsorbed *CO. This skillfully circumvents the further hydrogenation of *CO toward the C1 pathway, serving as the predominant factor through which a larger cation facilitates C-C coupling. This study unveils a comprehensive atomic mechanism of the cation-water-adsorbate interactions that can facilitate the further optimization of the electrolyte and EDL for efficient C-C coupling in CO2RR.

Heteroaromatic Hyperbranched Polyelectrolytes: Multicomponent Polyannulation and Photodynamic Biopatterning.

We reported an efficient multicomponent polyannulation for in situ generation of heteroaromatic hyperbranched polyelectrolytes by using readily accessible internal diynes and low-cost, commercially available arylnitriles, NaSbF6 , and H2 O/AcOH. The polymers were obtained in excellent yields (up to 99 %) with extraordinary high molecular weights (Mw up to 1.011×106 ) and low polydispersity indices. The resulting polymers showed good processibility and high quantum yields with tunable emission in the solid state, making them ideal materials for highly ordered fluorescent photopatterning. These hyperbranched polyelectrolytes also possessed strong ability to generate reactive oxygen species, which allowed their applications in efficient bacterial killing and customizable photodynamic patterning of living organisms in a simple and cost-effective way.

Polypyrrole coated hollow S/Co-doped carbon nanocages excels for packaging high-performance lithium sulfur batteries.

Although there are numerous virtues for lithium sulfur batteries, the notorious shuttle effect and insulated nature are impeding their practical application. To address these issues, here we report the design and synthesis of polypyrrole coated sulfur and cobalt co-doped carbon nanocages (PSCC). It demonstrates that both the performance and stability of the PSCC assisted Li-S batteries are improved. The hollow structure of PSCC bypassed the structural collapse effectively caused by volume expansion of sulfur during the reaction and physically suppressed shuttle effect of the intermediate product polysulfide lithium (LiPSs). Also, LiPSs was also trapped to inhibit the shuttle effect due to the strong adsorption of LiPSs via PSCC. In addition, PSCC can also provide an outstanding electronic conductivity, which will facilitate the next-step reaction of the absorbed LiPSs and enhance electrochemical reaction kinetics. Thus, the excellent rate performance was obtained with high specific discharge capacities of 1300 mAh g-1 at 0.1 C and 1000 mAh g-1 at 0.5 C. Such packaged high-performance positions our design for the ideal electrochemical energy storage devices.

NIR luminogen for low-temperature photothermal therapy by triggering HSP90α down-regulation.

A near-infrared (NIR) luminogen TST was designed and used to efficiently trigger HSP90α protein knockdown through photo-thermal conversion based on a gene interference strategy, by which in vitro and in vivo tumor ablation were significantly acquired at low-temperature.