Ge Zhongsheng, Wan Siyuan, Moin Muhammad, Moyez Sk Abdul, Dong Lizhuang, Haris Hamood Ur Rehman, Piotrowski Marek, Wang Zhiming, Leydecker Tim, Thumu Udayabhaskararao
Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610054, China.
Adv Sci (Weinh). 2025 Jul;12(28):e2417304. doi: 10.1002/advs.202417304. Epub 2025 Jun 5.
Lithium's interaction with CsPbBr nanocrystals (NCs), can enhancing its intrinsic electrical conductivity (σ) for high-performance device applications. Herein, two distinctly different modes of Li⁺ interaction with CsPbBr NCs: minor lattice insertion (0.07% relative to Cs) and predominant surface passivation is reported through LiPb alloy formation. In contrast, Li⁺ exhibits significantly reduced interaction with CsPbBr NCs, which could be due to the persence of lower amount of Pb on the surface of these structures. The σ of CsPbBr:xLi NCs through bottom-contact devices exhibited a gradual increase from 2.1 × 10 to as high as 2.5 × 10 S m, which is a 50-fold improvement compared to CsPbBr NCs. The enhanced σ is attributed to the presence of Li doping and surface passivation of CsPbBr by the LiPb ligated complexes. DFT calculations revealed electron movement from the valence and to conduction band and a reduced bandgap further supporting the inferences from experimental studies. The unique feature of the increased luminescence and σ of CsPbBr:Li NCs is explored for fabricating white light emitting diodes. The luminescence efficacy of the device is in the range of 88.5 to 112.5 lm W which is higher compared to pure CsPbBr NCs (96.5 lm W), offering a pathway for advanced optoelectronic applications.
锂与 CsPbBr 纳米晶体（NCs）的相互作用能够提高其本征电导率（σ），以用于高性能器件应用。在此，通过 LiPb 合金的形成，报道了 Li⁺与 CsPbBr NCs 两种截然不同的相互作用模式：少量晶格插入（相对于 Cs 为 0.07%）和主要的表面钝化。相比之下，Li⁺与 CsPbBr NCs 的相互作用显著降低，这可能是由于这些结构表面 Pb 的含量较低。通过底部接触器件的 CsPbBr:xLi NCs 的 σ 从 2.1×10 逐渐增加到高达 2.5×10 S m，与 CsPbBr NCs 相比提高了 50 倍。σ 的提高归因于 Li 掺杂的存在以及 LiPb 配位络合物对 CsPbBr 的表面钝化。密度泛函理论（DFT）计算揭示了电子从价带移动到导带以及带隙减小，进一步支持了实验研究的推断。探索了 CsPbBr:Li NCs 发光增强和 σ 增加的独特特性用于制造白光发光二极管。该器件的发光效率在 88.5 至 112.5 lm W 范围内，与纯 CsPbBr NCs（96.5 lm W）相比更高，为先进的光电子应用提供了一条途径。
