Qu Xiaodan, Hu Qiong, Song Zhongqian, Sun Zhonghui, Zhang Baohua, Zhong Jialing, Cao Xuyou, Liu Yuanjin, Zhao Bolin, Liu Zhenbang, Shen Yujie, Bao Yu, Wang Zhenxin, Zhang Yuwei, Niu Li
Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, University of Science and Technology of China, Changchun 130022, China.
Innovation (Camb). 2021 Jun 18;2(3):100137. doi: 10.1016/j.xinn.2021.100137. eCollection 2021 Aug 28.
A knowledge of the adsorption and desorption behavior of sorbates on surface adsorptive site (SAS) is the key to optimizing the chemical reactivity of catalysts. However, direct identification of the chemical reactivity of SASs is still a challenge due to the limitations of characterization techniques. Here, we present a new pathway to determine the kinetics of adsorption/desorption on SASs of graphene oxide (GO) based on total internal reflectance fluorescence microscopy. The switching on and off of the fluorescent signal of SAS lit by carbon dots (CDs) was used to trace the adsorption process and desorption process. We find that sodium pyrophosphate (PPi) could increase the adsorption equilibrium of CDs thermodynamically and promote the substrate-assisted desorption pathway kinetically. At the single turnover level, it was disclosed that the species that can promote desorption may also be an adsorption promoter. Such discovery provides significant guidance for improving the chemical reactivity of the heterogeneous catalyst.
了解吸附质在表面吸附位点（SAS）上的吸附和解吸行为是优化催化剂化学反应活性的关键。然而，由于表征技术的局限性，直接识别SAS的化学反应活性仍然是一个挑战。在此，我们提出了一种基于全内反射荧光显微镜来确定氧化石墨烯（GO）的SAS上吸附/解吸动力学的新途径。通过碳点（CDs）点亮的SAS荧光信号的开启和关闭来追踪吸附过程和解吸过程。我们发现焦磷酸钠（PPi）可以在热力学上增加CDs的吸附平衡，并在动力学上促进底物辅助的解吸途径。在单周转水平上，揭示了能够促进解吸的物种也可能是吸附促进剂。这一发现为提高多相催化剂的化学反应活性提供了重要指导。
