摘要
溶解浆和黏胶纤维工业每年产生大量结构为直链木聚糖的副产物,其开发利用是企业亟待解决的问题。本研究以副产物木聚糖为原料,将其溶解于NaOH溶液中通过水热反应制备光致发光木聚糖碳点(X-CDs),将制备的碳点掺入聚乙烯醇中制备荧光磷光双发射薄膜和磷光墨水,并对双发射薄膜的荧光、磷光性能进行深入研究。实验结果表明,透射电子显微镜显示X-CDs是平均粒径为3 nm的类球形,具有典型的石墨碳晶格衍射条纹;傅里叶变换红外光谱和X射线光电子能谱显示X-CDs主要组成元素为C和O,且表面存在羰基官能团,其产生的n→π^(*)跃迁能有效促进系间窜越产生室温磷光。X-CDs在溶液和固态状态下均具有荧光,但不显示室温磷光余晖效果,此时三线态激子容易被环境猝灭。将X-CDs掺杂进聚乙烯醇(PVA)中可产生具有激发波长依赖性的室温磷光余晖,表明PVA基质提供的氢键刚性环境可有效限制发光中心的旋转/振动,抑制了三线态激子的猝灭。将X-CDs和PVA溶液制成墨水,可应用于防伪、信息加密等领域。该研究为实用防伪材料的设计提供了新的思路,并拓宽了造纸厂副产物木聚糖的利用范围。
Due to the drawbacks of complexity,high cost,and toxicity associated with conventional room temperature phosphorescent(RTP) materials like pure-organic phosphorescent materials or metal-containing inorganic phosphorescent materials,carbon dot-based RTP materials have attracted widely attention because of their simple synthesis process,favorable photostability,and low biotoxicity compared to conventional phosphorescent materials in recent years.The unique properties of carbon dot based RTP materials have made them highly versatile and sought-after in various applications,including anti-counterfeiting,information encryption,sensors,and bioimaging.The dissolving pulp and viscose fiber industries produce a significant quantity of hemicellulose annually,which is a by-product characterized by a straight-chain xylan structure.However,the effective development and utilization of this by-product pose an urgent challenge for enterprises.To address this issue,this study focused on the preparation of photoluminescent xylan carbon dots(X-CDs) from industrial xylan through the one-pot hydrothermal reaction involving its dissolution in NaOH solution.The transmission electron microscopy(TEM) analysis revealed that the X-CDs exhibited a spherical-like morphology,with an average particle size of 3 nm,and displayed typical diffraction fringes associated with a graphitic carbon lattice.Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS) tests showed that the main constituent elements of X-CDs were C and O,and carbonyl functional groups were presented on the surface,and the n→π~* transition generated by X-CDs can effectively promote intersystem crossing to produce room temperature phosphorescence.X-CDs exhibited fluorescence in both solution and solid state,but did not show afterglow effects,since the triplet state exciton was easily quenched by the environment.The incorporation of X-CDs into polyvinyl alcohol(PVA) resulted in the generation of phosphorescent afterglows at room temperature,whic
作者
史美超
高倩
李岷钊
吕保中
彭锋
SHI Meichao;GAO Qian;LI Minzhao;LYU Baozhong;PENG Feng(Beijing Key Laboratory of Lignocellulosic Chemistry,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Efficient Production of Forest Resources,Beijing 100083,China)
出处
《林业工程学报》
CSCD
北大核心
2024年第6期93-98,共6页
Journal of Forestry Engineering
基金
国家杰出青年科学基金(32225034)
国家自然科学基金(22308028)。
关键词
木聚糖
碳点
室温磷光
余晖效果
防伪材料
双发射薄膜
磷光墨水
xylan
carbon dots
room-temperature phosphorescence
afterglow effect
anti-counterfeiting materials
dual emission thin film
phosphorescent ink
