Clean, Robust Alkali Sources by Intercalation within Highly-Oriented Pyrolytic Graphite

TL;DR

This paper introduces a novel rubidium vapor dispenser made from highly-oriented pyrolytic graphite intercalated with rubidium, offering higher capacity, lower power consumption, and reduced impurities compared to traditional dispensers.

Contribution

The authors develop and characterize a new type of vapor dispenser using intercalated graphite, demonstrating improved performance over commercial alternatives.

Findings

HOPG intercalation increases rubidium capacity by an order of magnitude.

Dispensers require significantly less heating power.

They emit fewer impurities and withstand atmospheric exposure.

Abstract

We report the fabrication, characterization, and use of rubidium vapor dispensers based on highly-oriented pyrolytic graphite (HOPG) intercalated with metallic rubidium. Compared to commercial chromate salt dispensers, these intercalated HOPG (IHOPG) dispensers hold an order of magnitude more rubidium in a similar volume, require less than one-fourth the heating power, and emit less than one-half as many impurities. Appropriate processing permits exposure of the IHOPG to atmosphere for over ninety minutes without any adverse effects. Intercalation of cesium and potassium into HOPG have also been demonstrated in the literature, which suggests that IHOPG dispensers may also be be made for those metals.