木质素基碳点的制备及其对pH响应分析  

Preparation of Lignin-based Carbon Dots and Analysis of Their Response to pH

作　　者：王楚楚 叶韧 史霄宇 刘玉鹏[1] 南静娅[1] 王春鹏[1] WANG Chuchu;YE Ren;SHI Xiaoyu;LIU Yupeng;NAN Jingya;WANG Chunpeng(Institute of Chemical Industry of Forest Products,CAF,Key Lab.of Biomass Energy and Material,Jiangsu Province,Key Lab.of Chemical Engineering of Forest Products,National Forestry and Grassland Administration,National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass,Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing 210042,China)

机构地区：[1]中国林业科学研究院林产化学工业研究所、江苏省生物质能源与材料重点实验室、国家林业和草原局林产化学工程重点实验室、林木生物质低碳高效利用国家工程研究中心、江苏省林业资源高效加工利用协同创新中心,江苏南京210042

出　　处：《林产化学与工业》2024年第4期107-112,共6页Chemistry and Industry of Forest Products

基　　金：国家重点研发计划资助项目(2023YFD2201405);江苏省生物质能源与材料重点实验室资助项目(JSBEM-S-202102)。

摘　　要：以碱木质素为原料,利用对甲苯磺酸进行酸解后再通过水热法制备了S掺杂的木质素基碳点(L-SCDs)。通过透射电镜(TEM)、红外光谱(FT-IR)、X射线光电子能谱(XPS)、紫外-可见吸收光谱(UV-vis)和荧光光谱(FL)对L-SCDs的形貌结构和光学性质进行表征分析,并探究了L-SCDs在不同pH环境下的响应性能。结果表明:L-SCDs主要由类石墨结构的碳核及其表面的发光单元组成,具有很好的分散性,平均粒径为2.19 nm;L-SCDs主要含有碳、氧、硫3种元素,其表面存在羟基、羰基、羧基等官能团,表明碱木质素与对甲苯磺酸发生了反应,S元素成功掺杂到L-SCDs中。L-SCDs在不同pH值下的荧光变化研究发现:L-SCDs在碱性环境下荧光强度显著下降,且pH值越大下降越明显,这主要是因为L-SCDs的发光单元中存在羧基,在碱性环境中形成羧酸盐,发光单元被破坏,荧光强度下降;而在酸性和中性环境下荧光强度无明显变化,表明L-SCDs具有选择性地对pH值响应的特性,可用于荧光探针检测酸碱性。The S-doped lignin-based carbon dots(L-SCDs)were prepared by hydrothermal method after acid hydrolysis of p-toluenesulfonic acid from alkali lignin.The morphology,structure and optical properties of L-SCDs were characterized by transmission electron microscopy(TEM),infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible absorption spectroscopy(UV-vis)and fluorescence spectroscopy(FL),and the response properties of L-SCDs in different pH environments were investigated.The results showed that L-SCDs was mainly composed of graphite-like carbon nuclei and luminescent units on their surfaces,and it had good dispersion with an average particle size of 2.19 nm.L-SCDs mainly contained three elements of carbon,oxygen and sulfur,and there were hydroxyl,carbonyl,carboxyl and other functional groups on their surface,indicating that alkali lignin reacted with p-toluenesulfonic acid and S element was successfully doped into L-SCDs.The study on the fluorescence changes of L-SCDs at different pH values showed that the fluorescence intensity of L-SCDs decreased significantly in alkaline environment,and the decrease was more obvious with the increase of pH value,which was mainly owing to the existence of carboxyl groups in the luminous unit of L-SCDs.The carboxylate was formed in alkaline environment,the luminous unit was destroyed,and the fluorescence intensity decreased.However,there was no significant change in acidic and neutral environment,indicating that L-SCDs had the characteristic of selective response to pH and could be used as a fluorescent probe to detect acid-alkalinity.

关 键 词：碱木质素 碳点 荧光 PH响应 

分 类 号：TQ35[化学工程]