Viyada Harnchana

Interfacial instability and sluggish kinetics of high-purity aluminum (Al) anodes remain major bottlenecks for rechargeable nonaqueous aluminum-ion batteries (AIBs) to achieve high electrochemical performance. This study systematically evaluates the effects of alloying compositions on dendrite formation in commercial AA1235, AA3003, and AA8006 Al alloys as scalable, high-performance and low-cost anodes in chloroaluminate-based electrolyte AIBs. Comprehensive results demonstrate that the commercial Al alloys achieve superior cycling stability over pure Al metal benefited by leveraging a balanced intermetallic distribution that promotes uniform Al plating and suppresses vertical dendrite propagation. In contrast, high-purity Al exhibits limited long-life cycles due to its inhomogeneous native oxides. Our findings reveal that tailored commercial alloys can outperform their high-purity materials, offering a strategic pathway for durable and cost-effective energy storage based on multivalent metal-ion chemistries.

Understanding the underlying principles of contact electrification is critical for more efficient triboelectric nanogenerator (TENG) development. Herein, we use ReaxFF molecular dynamics simulations in conjunction with a charge equilibration method to investigate the contact electrification mechanism in polyisoprene (PI), a natural rubber polymer, when it comes into contact with copper (Cu) and polytetrafluoroethylene (PTFE). The simulations reveal that the charge transfer directions in the PI/Cu and PI/PTFE contact models are opposite, and the amount of charge transfer in the former is substantially less than that in the latter, which are consistent with our TENG measurements. Contact electrification is revealed to be a spontaneous process that occurs to lower electrostatic energy, and the electrostatic energy released during contact electrification of PI/PTFE is greater than that of PI/Cu, which can be correlated with the relative strength of triboelectric charging observed for the two systems. A compression simulation of the PI/Cu contact model reveals that the quantity of charge transfer grows exponentially as compressive strain increases. Despite increasing the total energy of the system due to densification and distortion of the polymer structure, the applied deformation results in an energetically more stable electrostatic arrangement. We also find that the incorporation of a carbonaceous material into a polyisoprene matrix causes a faster increase in the amount of charge transfer with compressive strain, which is governed by a steeper electrostatic energy profile. This study provides an alternative perspective on the contact electrification mechanism, which could be beneficial for the development of energy harvesting devices.