Interfacial
effect has attracted increasing interest as the inherent
asymmetric environment of a gas–liquid interface leads to different
chemical and physical properties between this region and the bulk
phase, resulting in enhanced chemical processes, specific reactions,
and mass transfer at the interface. Photochemical vapor generation
(PVG) is regarded as a simple and green sample introduction method
in atomic spectrometry. However, the photochemical behavior of elements
with the interface is not known. Herein, we report the PVG of elements
at the gas–liquid interface along with a possible mechanism
investigated for the first time. Enhancement and/or suppression effects
from the gas–liquid interface were observed on the PVG of 17
elements, which was correlated with the properties of analytes and
the generated intermediate substances/products of PVG and the applied
conditions. Enhancement from 1.1- to 7.3-fold in analytical sensitivity
was found for 12 elements in the system with gas–liquid interface(s)
compared to the results obtained in previous reports of PVG using
traditional flow injection with inductively coupled plasma mass spectrometry
measurement. The introduction of gas–liquid interface(s) and
the resultant elevated temperature inside the PVG reactor likely facilitated
the generation of radicals, the subsequent radical-based reactions,
and the separation/transport/detection of volatile species of elements.
In contrast, intermediate substances/products generated in PVG with
poor thermostability will readily decompose at elevated temperatures,
leading to a decreased signal response of analytes. The finding is
helpful to understand the transport of elements under UV irradiation
in the environment and has potential for analysis of trace elements
in environmental and biological samples.