摘要
Room-temperature phosphorescence(RTP)materials play a vital role in security domain due to their unique optical properties.However,most average lifetimes of available RTP materials remain less than 1 s in aqueous-phase media,which is unfavorable to practical applications.Herein,an ex-situ covalent coupling strategy is proposed to fabricate liquid-phase long-lived RTP materials by combining SiO_(2)microspheres with the feather-derived carbon dots(CDs).Astonishingly,the aqueous dispersion of the resulting CDs@SiO_(2)microspheres exhibits a lifetime of up to 2.38 s with an absolute quantum yield of 22%.Moreover,the average lifetime of the solid CDs@SiO_(2)is as long as 3.04 s,which is superior to that of existing RTP carbon-based materials.The striking enhancements in the RTP of the CDs@SiO_(2)composites are mainly attributed to the immobilization of the formed Si–O–C covalent bonds and Si–O–Si rigid networks.The CDs@SiO_(2)composites were subsequently applied in the fields of information encryption and anti-fake.Interestingly,the CDs@SiO_(2)composites possess intriguing,reversible and stable optical properties,including water-responsive structural colors,blue fluorescence and cyan RTP,exhibiting excellent covert performance in applications of information encryption and decryption,and high-level anticounterfeiting.These findings provide not only a straightforward strategy for developing multiresponsive optical materials but also a more secure anticounterfeiting technology.
室温磷光(RTP)材料具有独特的光学特性,在安全领域发挥着重要作用.然而,现有RTP材料在水相介质中的平均寿命大多小于1 s,不利于实际应用.本文提出了一种原位共价偶联策略,通过将二氧化硅微球与羽毛衍生的碳点(CDs)结合,制备液相长寿命RTP材料.令人惊奇的是,所制备的水分散的CDs@SiO_(2)微球的RTP寿命长达2.38 s,绝对量子产率为22%.同时,固态CDs@SiO_(2)的平均寿命长达3.04 s,优于现有的RTP碳基材料.形成的Si–O–C共价键和Si–O–Si刚性网络的固定作用导致了CDs@SiO_(2)的RTP的显著增强.随后,CDs@SiO_(2)复合材料被分别应用于信息加密和防伪领域.有趣的是,CDs@SiO_(2)复合材料具有有趣、可逆和稳定的光学特性,包括水响应结构色、蓝色荧光和青色RTP,在信息加解密和高级防伪应用中表现出优异的隐蔽性能.这些发现不仅为开发多响应光学材料提供了一种直接的策略,而且提供了一种更加安全的防伪技术.
基金
the National Natural Science Foundation of China(52173206)
the Applied Foundation Frontier Project from Wuhan Science and Technology Bureau(2022013988065202)。
