The visualization of accurate colour information using quantum dots has been explored for decades, and commercial products employing environmentally friendly materials are currently available as backlights1. However, next-generation electroluminescent displays based on quantum dots require the development of an efficient and stable cadmium-free blue-light-emitting device, which has remained a challenge because of the inferior photophysical properties of blue-light-emitting materials2,3. Here we present the synthesis of ZnSe-based blue-light-emitting quantum dots with a quantum yield of unity. We found that hydrofluoric acid and zinc chloride additives are effective at enhancing luminescence efficiency by eliminating stacking faults in the ZnSe crystalline structure. In addition, chloride passivation through liquid or solid ligand exchange leads to slow radiative recombination, high thermal stability and efficient charge-transport properties. We constructed double quantum dot emitting layers with gradient chloride content in a light-emitting diode to facilitate hole transport, and the resulting device showed an efficiency at the theoretical limit, high brightness and long operational lifetime. We anticipate that our efficient and stable blue quantum dot light-emitting devices can facilitate the development of electroluminescent full-colour displays using quantum dots.

中文翻译：

---

高效稳定的蓝色量子点发光二极管

几十年来，人们一直在探索使用量子点实现准确颜色信息的可视化，目前采用环保材料的商业产品可用作背光源1。然而，基于量子点的下一代电致发光显示器需要开发一种高效稳定的无镉蓝光发射器件，由于蓝光发射材料的光物理性能较差2、3，这一直是一个挑战。在这里，我们提出了具有统一量子产率的基于 ZnSe 的蓝光发射量子点的合成。我们发现氢氟酸和氯化锌添加剂可通过消除 ZnSe 晶体结构中的堆垛层错来有效提高发光效率。此外，通过液体或固体配体交换的氯化物钝化导致缓慢的辐射复合、高热稳定性和有效的电荷传输特性。我们在发光二极管中构建了具有梯度氯化物含量的双量子点发射层，以促进空穴传输，所得器件显示出理论极限的效率、高亮度和长使用寿命。我们预计，我们高效且稳定的蓝色量子点发光器件可以促进使用量子点的电致发光全彩显示器的开发。所得器件显示出理论极限的效率、高亮度和长使用寿命。我们预计，我们高效且稳定的蓝色量子点发光器件可以促进使用量子点的电致发光全彩显示器的开发。所得器件显示出理论极限的效率、高亮度和长使用寿命。我们预计，我们高效且稳定的蓝色量子点发光器件可以促进使用量子点的电致发光全彩显示器的开发。