Clark Pip C J, Flavell Wendy R
School of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester, M13 9PL, UK.
Present address: Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner Platz 1, D-14109 Berlin, Germany.
Chem Rec. 2019 Jul;19(7):1233-1243. doi: 10.1002/tcr.201800085. Epub 2018 Nov 2.
Control of the surface and interface chemistry of colloidal quantum dots (CQDs) is critical to achieving a product with good air stability and high performing optoelectronic devices. Through various surface passivation treatments, vast improvements have been made in fields such as CQD photovoltaics; however devices have not currently reached commercial standards. We show how X-ray photoelectron spectroscopy (XPS) can provide a better understanding of exactly how surface treatments act on CQD surfaces, and the effect of surface composition on air stability and device performance.. We illustrate this with PbS-based CQDs, using XPS to measure oxidation processes, and to quantify the composition of the topmost surface layer after different surface treatments. We also demonstrate the use of synchrotron radiation-excited depth-profiling XPS, a powerful technique for determining the surface composition, chemistry and structure of CQDs. This review describes our recent progress in characterization of CQD surfaces using SR-excited depth profiling XPS and other photoemission techniques.
控制胶体量子点（CQD）的表面和界面化学对于获得具有良好空气稳定性的产品和高性能光电器件至关重要。通过各种表面钝化处理，CQD光伏等领域已取得了巨大进步；然而，目前器件尚未达到商业标准。我们展示了X射线光电子能谱（XPS）如何能更好地理解表面处理究竟如何作用于CQD表面，以及表面组成对空气稳定性和器件性能的影响。我们以基于PbS的CQD为例进行说明，使用XPS测量氧化过程，并量化不同表面处理后最表层的组成。我们还展示了同步辐射激发深度剖析XPS的应用，这是一种用于确定CQD表面组成、化学性质和结构的强大技术。本综述描述了我们最近在使用同步辐射激发深度剖析XPS和其他光发射技术表征CQD表面方面取得的进展。
