摘要
内建电场被认为是促进电荷迁移和分离,以提高光催化性能的有效驱动因素。本工作通过一步溶剂热法合成了间隙氯和取代氯共掺杂的一维纳米棒Mn_(0.2)Cd_(0.8)S(MCS)。间隙氯和取代氯的掺杂导致MCS纳米棒中的电荷分布不平衡,形成内建电场,有利于提高光生载流子动力学。通过密度泛函理论计算,本研究直观地描述了间隙氯和取代氯的掺杂对MCS活性的影响,包括电子结构、电荷分布和H2吸附/解吸平衡的差异。有趣的是,MCS能带结构的调制主要源于间隙氯的贡献,而取代氯无贡献。同时,取代氯可以进一步促进间隙氯对MCS的H_(2)吸附-脱附吉布斯自由能的优化。最终,0.9 Cl-MCS的H2吸附-脱附吉布斯自由能更有利于H_(2)的产生(1.14 vs.0.17 eV),光催化H2的产生活性提高了9倍。本研究为在双金属硫化物光催化剂中构建内建电场提供了有价值的途径。
The construct of the internal electric field(IEF)is recognized as an effective driver for promoting charge migration and separation to enhance photocatalytic performance.In this study,onedimensional nanorods of Mn_(0.2)Cd_(0.8)S(MCS)co-doped with interstitial chlorine(Cl_(int))and substitutional chlorine(Cl_(sub))were designed and synthesized using a one-step solvothermal method.The incorporation of Cl_(int) and Cl_(sub) led to an unbalanced charge distribution and the formation of IEF in the MCS nanorods,contributing to the improvement of photogenerated carrier kinetic behavior.Through density functional theory(DFT)calculations,the effect of Cl_(int) and Cl_(sub) doping on the activity of the MCS was visually explained by examining differences in electronic structure,charge distribution and H_(2) adsorption/desorption balance.Interestingly,the modulation of the energy band structure of MCS primarily resulted from the contribution of Clint,while Clsub playing a negligible role.Moreover,the Clsub further facilitated the optimization of Clint concerning the H_(2) adsorption-desorption Gibbs free energy(ΔG_(H*))of MCS.Ultimately,the ΔG_(H*)of 0.9 Cl-MCS favored H_(2) production(1.14 vs.0.17 eV),leading to a 9 times increase in photocatalytic H_(2) production activity compared to MCS.This investigation presents a valuable approach for constructing IEF in bimetallic sulfide photocatalysts.
作者
孙培培
张锦源
宋艳华
莫曌
陈志刚
许晖
Peipei Sun;Jinyuan Zhang;Yanhua Song;Zhao Mo;Zhigang Chen;Hui Xu(School of the Environment and Safety Engineering,Jingjiang College,Jiangsu University,Zhenjiang 212013,Jiangsu Province,China;School of Environmental and Chemical Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,Jiangsu Province,China)
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2024年第11期21-22,共2页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(22378174,21878134,22208129,22108110)资助。
关键词
光催化
产氢
双金属硫化物
内建电场
吉布斯自由能
Photocatalysis
H_(2) production
Bimetallic sulfides
Internal electric fields
Gibbs free energy
