Guo Xin, Sun Xuening, Zhang Jinfeng, Huang Yuanfen, Liu Xiaohong, Liu Xin, Xu Weilin, Chen Dongzhi
State Key Laboratory of New Textile Materials & Advanced Processing Technology, Wuhan Textile University, Wuhan, 430073, P. R. China.
School of Materials Science and Engineering, Wuhan Textile University, Wuhan, 430200, P. R. China.
Small. 2024 Jan;20(2):e2303464. doi: 10.1002/smll.202303464. Epub 2023 Sep 5.
Silicon nanocrystals (SiNCs) have attracted extensive attention in many advanced applications due to silicon's high natural abundance, low toxicity, and impressive optical properties. However, these applications are mainly focused on fluorescent SiNCs, little attention is paid to SiNCs with room-temperature phosphorescence (RTP) and their relative applications, especially water-dispersed ones. Herein, this work presents water-dispersible RTP SiNCs (UA-SiNCs) and their optical applications. The UA-SiNCs with a uniform particle size of 2.8 nm are prepared by thermal hydrosilylation between hydrogen-terminated SiNCs (H-SiNCs) and 10-undecenoic acid (UA). Interestingly, the resultant UA-SiNCs can exhibit tunable long-lived RTP with an average lifetime of 0.85 s. The RTP feature of the UA-SiNCs is confirmed to the n-π* transitions of their surface C═O groups. Subsequently, new dual-modal emissive UA-SiNCs-based ink is fabricated by blending with sodium alginate (SA) as the binder. The customized anticounterfeiting labels are also prepared on cellulosic substrates by screen-printing technique. As expected, UA-SiNCs/SA ink exhibits excellent practicability in anticounterfeiting applications. These findings will trigger the rapid development of RTP SiNCs, envisioning enormous potential in future advanced applications such as high-level anti-counterfeiting, information encryption, and so forth.
由于硅的天然丰度高、毒性低且具有令人印象深刻的光学性质，硅纳米晶体（SiNCs）在许多先进应用中引起了广泛关注。然而，这些应用主要集中在荧光SiNCs上，对具有室温磷光（RTP）的SiNCs及其相关应用，尤其是水分散性的SiNCs关注较少。在此，这项工作展示了水分散性RTP SiNCs（UA-SiNCs）及其光学应用。通过氢封端的SiNCs（H-SiNCs）与10-十一碳烯酸（UA）之间的热硅氢化反应制备了粒径均匀为2.8 nm的UA-SiNCs。有趣的是，所得的UA-SiNCs可以表现出可调谐的长寿命RTP，平均寿命为0.85 s。UA-SiNCs的RTP特性被证实是其表面C═O基团的n-π*跃迁。随后，通过与作为粘合剂的海藻酸钠（SA）混合制备了新型双模态发射的基于UA-SiNCs的墨水。还通过丝网印刷技术在纤维素基材上制备了定制的防伪标签。正如预期的那样，UA-SiNCs/SA墨水在防伪应用中表现出优异的实用性。这些发现将推动RTP SiNCs的快速发展，预示着其在未来高级应用如高级防伪、信息加密等方面具有巨大潜力。
