The recent introduction of nanoporous ion emitters (nano-PIEs) formed from metal-organic frameworks (MOFs) has demonstrated their potential to enhance sensitivity for thermal ionization mass spectrometry (TIMS). Nano-PIEs take advantage of the parent MOF's chemical and structural tunability to form scaffolds for ion emitters. A study by Barpaga et al., 2023 on MOF-74 as the parent material found that with high volatility metals in their framework, uranium sample utilization efficiency (SUE) increases by up to 9-fold (e.g., Zn-MOF-74) compared to that of the analyte on a bare filament (∼0.05%). In this study, we investigate the performance of Zn-MOF-74 to maximize uranium efficiencies at the trace level (= 10