Eroles Franco, López Yesica Celeste Villagrán, López María Beatriz, Zoloff Michoff Martin E, Luque Guillermina, Cometto Fernando
Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Fisicoquímica, X5000HUA Córdoba, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones en Fisicoquímica de Córdoba (INFIQC), X5000HUA Córdoba, Argentina.
Phys Chem Chem Phys. 2025 Jan 29;27(5):2631-2643. doi: 10.1039/d4cp04183f.
Metallic lithium plays an important role in the development of next-generation lithium metal-based batteries. However, the uncontrolled growth of lithium dendrites limits the use of lithium metal as an anode. In this context, a stable solid electrolyte interphase (SEI) is crucial for regulating dendrite formation, stability, and cyclability of lithium metal anodes. This article proposes an artificial protective layer of P-doped carbon nitride on the lithium anode surface to address these issues. A thin film of P-doped carbon nitride (CNP) was created through a simple drop-casting method using synthesized CNP powder, forming an artificial SEI on the lithium electrode. The resulting symmetric CNP-modified Li/Li cells exhibited remarkable cyclability with low overpotentials of around 40 mV over 500 cycles at a current density of 3 mA cm. Anode degradation and SEI composition were thoroughly studied for cycled electrodes to gain insight into the mechanisms underlying this modified surface. Furthermore, these CNP-modified anodes were successfully utilized in a Li-S coin cell battery, achieving high capacity and capacity retention at a high current density (1C). First-principles calculations indicate that P-doping in the carbon nitride structure significantly enhances the surface diffusion of lithium and promotes more homogeneous lithium plating.
金属锂在下一代锂金属基电池的发展中起着重要作用。然而，锂枝晶的无控制生长限制了锂金属作为阳极的使用。在这种情况下，稳定的固体电解质界面（SEI）对于调节锂金属阳极的枝晶形成、稳定性和循环性能至关重要。本文提出在锂阳极表面制备一层P掺杂的氮化碳人工保护层来解决这些问题。通过使用合成的CNP粉末，采用简单的滴铸法制备了P掺杂的氮化碳（CNP）薄膜，在锂电极上形成了人工SEI。所得的对称CNP修饰的Li/Li电池表现出显著的循环性能，在3 mA cm的电流密度下，500次循环中过电位低至约40 mV。对循环电极的阳极降解和SEI组成进行了深入研究，以深入了解这种修饰表面的潜在机制。此外，这些CNP修饰的阳极成功应用于锂硫硬币电池中，在高电流密度（1C）下实现了高容量和容量保持率。第一性原理计算表明，氮化碳结构中的P掺杂显著增强了锂的表面扩散，并促进了更均匀的锂沉积。
