摘要
染料敏化太阳能电池(DSSCs)的对电极一般采用贵金属铂(Pt),但Pt在碘系电解液中易被腐蚀,导致DSSCs成本较高且稳定性不足,难以规模化生产。以可再生木质素为碳源制备高性能电催化剂作为Pt对电极的廉价替代品无疑是一种理想策略。以木质素为碳源、KOH为活化剂,通过一步热解法合成了多级多孔碳,并应用于DSSCs。通过扫描电镜、X射线衍射仪、拉曼光谱仪及全自动比表面积分析仪等方法研究了多孔碳的结构特征及孔隙特性,利用电化学工作站、太阳光模拟器、万用电表等设备评估了该衍生碳作为DSSCs对电极材料催化I-3还原的能力。结果表明,木质素衍生多孔碳材料具有优异的催化活性,比表面积高达530.54 m^(2)/g,总孔容为0.64 cm^(3)/g,且同时具有微孔、中孔和大孔。其器件短路电流密度、开路电压及光电转换效率分别达到了15.88 mA/cm^(2)、710 mV和7.27%,远高于活化前,甚至超过了Pt基电池,展现了其在DSSCs领域的应用潜力。综上所述,通过简单的共热解方法,KOH和木质素成功合成了多级多孔碳材料,其高比表面积和丰富的孔隙可实现电荷的快速转移,从而显著提升了电化学性能。因此,该多孔碳作为DSSCs对电极时,能显著提高器件的各个参数,并获得高于Pt基DSSCs的转换效率,表明木质素衍生碳具有作为Pt对电极廉价替代品的潜力。
In traditional dye⁃sensitized solar cells(DSSCs),platinum(Pt)is commonly employed as the counter electrode due to its excellent electrical conductivity.However,the susceptibility of Pt to corrosion in iodide⁃based electrolytes results in high cost and inadequate stability,which hinders the scalability of production.On the other hand,lignin,as one of the primary components of plant cell walls,boasts a high carbon content(64.2%),a unique aromatic structure,porosity,a high degree of polymerization,adjustability,and functionalizability,as well as the advantages of being renewable and environmentally benign.These attributes confer notable benefits in electrochemical applications,such as supercapacitors,sensors,and DSSCs.Thus,utilizing renewable lignin as a carbon source to synthesize a high⁃performance electrocatalyst as a cost⁃effective substitute for the Pt counter electrode represents an ideal strategy.Hierarchical porous carbon was synthesized using lignin as a carbon source and KOH as an activator and applied to DSSCs.The structural characteristics and pore properties of the porous carbon were studied using the scanning electron microscope,X⁃ray diffractometry,Raman spectroscopy,and automatic specific surface area and porosity analyzers.The electrocatalytic ability of the derived carbon as a counter electrode material for I-3 reduction in DSSCs was evaluated using an electrochemical workstation,a solar simulator,a multimeter,and other equipment.The findings indicated that the optimal pore characteristics were achieved when lignin was combined with KOH at a mass ratio of 1∶4,yielding lignin⁃derived porous carbon with an impressive specific surface area of 530.54 m^(2)/g and a total pore volume of 0.64 cm^(3)/g.The coexistence of micropores,mesopores and macropores endows the porous carbon material with exceptional catalytic activity.The short⁃circuit current density,open⁃circuit voltage,and photoelectric conversion efficiency of the device reached 15.88 mA/cm^(2),710 mV and 7.27%,respectively,which were much higher than those before activation and even higher than Pt⁃based cells,demonstrating high application potential in the field of DSSCs.Through the straightforward co⁃pyrolysis of KOH and lignin,hierarchical porous carbon materials were effectively synthesized.The abundant pores and high surface area of these materials facilitated rapid charge transfer,leading to substantial improvements in electrochemical performance.Notably,utilizing the porous carbon material as the counter electrode in DSSCs led to substantial improvements across different device parameters,resulting in a conversion efficiency that surpassed that of Pt⁃based DSSCs.These results suggested that lignin⁃derived carbon materials possess strong potential as an economical and viable alternative to Pt⁃based counter electrodes in DSSCs technology.
作者
柴化云
程文杰
柴亚玲
万才超
吴义强
CHAI Huayun;CHENG Wenjie;CHAI Yaling;WAN Caichao;WU Yiqiang(College of Materials Science and Engineering,Central South University of Forestry&Technology,Changsha 410004,China)
出处
《林业工程学报》
北大核心
2025年第1期33-40,共8页
Journal of Forestry Engineering
基金
国家万人计划青年拔尖项目(SQ2022QB07490)
国家自然科学基金青年科学基金(31901249)
中国科协青年人才托举工程项目(2019QNRC001)。
关键词
木质素
多级多孔碳
染料敏化太阳能电池
对电极
电化学性能
lignin
hierarchical porous carbon
dye⁃sensitized solar cell
counter electrode
electrochemical performance
作者简介
柴化云,女,研究方向为生物质基功能材料;通信作者:万才超,男,教授。E⁃mail:wancaichaojy@163.com。
