Work function (WF) of a material is not only an intrinsic characteristic of bulk but also a surface property. The measurement and control of WF have been of great concern in many electronic and optical devices as the WF governs charge transfer and charge injection/collection efficiency at interfaces and emission characteristics of conventional charged particle emitters. Photoelectron spectroscopy (PES) has been mainly used to determine surface electronic structure and chemical composition. Despite the common use of this technique to measure WF, there has been a lack of discussion on how to use the PES and what to be considered to determine the absolute WF. The main contribution of this review lies in the discussion of the causes of errors when measuring WF, and provides a guide for reliable WF measurement. Along with the limitations of current measurement technology, we propose future directions for absolute WF measurement.

材料的功函数 (WF) 不仅是体积的固有特性，也是表面特性。WF 的测量和控制在许多电子和光学设备中备受关注，因为 WF 控制着界面处的电荷转移和电荷注入/收集​​效率以及传统带电粒子发射器的发射特性。光电子能谱（PES）主要用于确定表面电子结构和化学成分。尽管普遍使用这种技术来测量 WF，但缺乏关于如何使用 PES 以及考虑什么来确定绝对 WF 的讨论。本综述的主要贡献在于讨论了测量 WF 时的误差原因，并为可靠的 WF 测量提供了指导。