Zinc-Adeninate Metal–Organic Framework: A Versatile Photoluminescent Sensor for Rare Earth Elements in Aqueous Systems

Abstract

Rare earth elements (REEs) are strategically important for national security and advanced technologies. Consequently, significant effort has been devoted towards increasing REE domestic production, including the extraction of REEs from coal, coal combustion byproducts, and their associated waste streams such as acid mine drainage. Analytical techniques for rapid quantification of REE content in aqueous phases can facilitate REE recovery through rapid identification of high-value waste streams. In this work, we show that BioMOF-100 can be used as a fluorescent-based sensitizer for emissive REE ion detection in water, providing rapid (<10 min) analysis times and sensitive detection (parts-per-billion detection limits) for terbium, dysprosium, samarium, europium, ytterbium, and neodymium, even in the presence of acids or secondary metals.

Metal–organic framework thin films as versatile chemical sensing materials

“…84,85 Photofunctionality can be introduced into MOF thin films through a variety of ways: 86 the use of chromophoric organic linkers within the MOF structures, 87 optically-active metal centers (particularly emissive lanthanides), 88 or via host-guest interactions, in which photoactive ions, 89,90 metal complexes, 91,92 molecules, 93-96 nanoparticles, 97-100 and/or other species are encapsulated by the MOF. MOF-based optical sensors are intriguing because they typically exhibit rapid response times (often on the order of seconds), [101][102][103][104] high sensitivity (ppb or lower LOD), 103,105,106 recyclability (via removal of analyte from the MOF after each sensing cycle), 103,104,[107][108][109] and usually can be integrated with inexpensive, portable equipment, 90 such as fiber optic-based platforms. 104,110,111 Indeed, many optical sensors allow for naked-eye detection of analytes and require only simple laser pointers, lightemitting diodes, UV lamps, or other portable excitation sources for operation.…”

“…Common luminescent guests include lanthanides, 101,162 emissive nanoparticles, 159 metal complexes, 136 and organic molecules. 147…”

“…149 Ion Sensors: The rapid, sensitive, and selective detection of ions has utility in a wide range of areas, including prospecting for high-value elements, 90 identifying heavy metal contaminants in water sources, 127,131 and medical diagnostics. 103,132 Please do not adjust margins Please do not adjust margins through binding sites within the MOF, 103,131 or through electrostatic interactions 101 (e.g. the use of a cationic MOF to sense anions and anionic MOFs to sense cations).…”

Quantum Sensing for Energy Applications: Review and Perspective

“…MOFs are highly organized, porous, crystalline structures comprised of metal cluster centers connected by organic molecular linkers, and have been extensively used for sensing applications, [ 178 ] including in energy‐relevant areas such as the detection of gases, [ 179 ] pH, [ 180 ] and rare earth ions. [ 181 ] Hence, the integration of qubits into the MOF structure may pave the way for the quantum sensing of analytes taken into the MOF pores, thereby enhancing existing MOF‐based sensing technologies. [ 182 ] Several MOFs to date have been designed with highly ordered qubit arrays based on cobalt (II), [ 183 ] copper (II), [ 182,184 ] and vandyl [ 185 ] spins, representing an intriguing class of next‐generation quantum materials ( Figure ).…”

“…The detection of magnetic ions may also be useful for monitoring corrosion in real‐time and in the sensing of critical metals such as rare earth elements (REEs), which are found in coal, fly ash, and acid mine drainage. [ 181 ] Commercially available quantum gravitometers and atomic clocks are already being used for oil and gas exploration, as discussed in Section 2.4. The integration of quantum materials into sensing‐relevant platforms and devices (discussed in the next section) represents an exciting new frontier in the development of high‐performance field‐deployable sensors for energy applications and beyond.…”