Custom-built light-pipe cell for high-resolution infrared absorption spectroscopy of tritiated water vapor and other hazardous gases

Abstract

We present a new custom-built cell for high-resolution absorption spectroscopy of hazardous gases. The use of an aluminum light-pipe enables sensitive detection due to the small tube diameter and an increased particle density in the interaction volume for a limited analyte amount in the cell, while avoiding additional surfaces such as mirrors. To demonstrate this, we have used the cell to measure tritiated water isotopologues (HTO and traces of T 2 O) for which spectroscopic data is scarce, due to the challenge of performing spectroscopy of these highly radio-chemical aggressive substances. For this purpose, the new cell also features the efficient inline-production of tritiated water. In this paper we present the concept of the light-pipe cell and demonstrate its performance with a high-resolution absorption spectrum of gaseous HTO generated inside of this cell.

Accurate Reference Gas Mixtures Containing Tritiated Molecules: Their Production and Raman-Based Analysis

“…For instance, mixtures of various hydrogen isotopologues were processed using a copper oxide reduction process to generate tritiated water vapor samples. These were then used in high-resolution FTIR studies of HTO [ 60 , 61 ].…”

Development of 2.2 μm cavity ring-down spectrometer for tritiated water analysis

“…For tritium, optical spectroscopic data were obtained by several different techniques, such as laser absorption spectroscopy, Fourier transform infrared spectroscopy, and CRDS. [12][13][14][15][16][17][18] However, a quantitative analytical system for tritium based on laser spectroscopy has not yet been realized. Therefore, we are developing a cavity ring-down spectrometer for tritium analysis.…”