摘要
采用水热法和低温浸渍法制备了电子助剂还原石墨烯(rGO)和界面活性位点Ni(Ⅱ)共修饰的高效TiO_2光催化剂(简称Ni(Ⅱ)/TiO_2-rGO)。制氢性能测试结果表明:相比于TiO_2和单独还原石墨烯复合的TiO_2,经还原石墨烯与Ni(Ⅱ)协同修饰后的TiO_2表现出更高的光催化制氢性能。其中,Ni(Ⅱ)/TiO_2-rGO(0.1 mol·L-1)具有最高制氢性能,制氢速率达到77.0μmol·h-1,分别是TiO_2(16.4μmol·h-1)和TiO_2-rGO(28.0μmol·h-1)的4.70倍和2.75倍。还原石墨烯助剂与Ni(Ⅱ)活性位点协同增强制氢性能的原理是:还原石墨烯作为电子助剂可以快速捕获和传输电子,Ni(Ⅱ)作为界面活性位点可以从溶液中捕获H+,提高界面反应速率,2种助剂协同作用加快了TiO_2上的光生电子-空穴对的有效分离。
Highly efficient TiO： photocatalysts co-modified by reduced graphene oxide （rGO） as electron -transfer mediator and Ni（Ⅱ） as interracial catalytic active-sites （referred to as Ni（Ⅱ）/TiO2-rGO） were synthesized via a two- step process including the initial hydrothermal method of rGO on the TiO2 surface and the following low- temperature impregnation method of Ni （Ⅱ） on the rGO. Photocatalytic experimental results indicated that all resulted Ni（Ⅱ）/TiO2-rGO photocatalysts exhibited obviously high H2-production performance. The highest Hz- production rate of the resultant Ni（Ⅱ）/TiO2-rGO （0.1 mol-L-1） reached 77.0 p, mol. h-1, while this value was higher than that of the TiO2 （16.4μ mol＇h-） and TiO2-rGO （28.0 μmol.h-1） by a factor of 4.70 and 2.75, respectively. On the basis of the experimental resuhs,a synergistic effect mechanism of rGO and Ni（Ⅱ） bi-cocatalysts was proposed to account for its enhanced H2-production performance, namely, rGO functions as an electron-transfer mediator to rapidly capture and transfer the photogenerated electron from TiO2 surface, while the Ni（Ⅱ） cocatalyst serves as an effectively active site for the following reduction.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2017年第7期1132-1138,共7页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金(No.21477094)
国家级大学生创新创业训练计划项目(No.20161049720001)资助
关键词
TIO2
协同效应
还原石墨烯
电子助剂
Ni(Ⅱ)
界面活性位点
TiO2
synergistic effect
reduced graphene oxide （rGO）
electron-transfer mediator
Ni（Ⅱ）
interfacial catalytic active-site
