Mixed metal (cobalt/molybdenum) based metal-organic frameworks for highly sensitive and specific sensing of arsenic (V): Spectroscopic versus paper-based approaches

A Review of Metal–Organic Framework‐Based Compounds for Environmental Applications

“…[430,431] Of them, the construction of the catalysis systems (such as photocatalytic and electrocatalytic systems) is considered to be a potential method for the efficient detection of heavy metal ions. [432,433] Owing to the superior porosity, large specific surface area, good adsorption ability, and rich surface functional groups, [434,435] MOF-based compounds have received significant research interest for the detection of different types of heavy metal ions, such as Cr (VI), [436,437] Pb(II), [438,439] Fe(III), [440,441] Hg(II), [442,443] Cd (II), [444,445] As(III), [446,447] Cu(II), [448,449] Co(III), [450,451] and Al (III). [452,453] For example, in 2021, Hussain et al [437] designed the UiO-66-NH 2 @BiOCl composite as an efficient photocatalyst for the reduction of Cr(VI) to Cr(III).…”

A blue arsenomolybdic acid-crystal violet ion-associate pair paving the way for the field detection of arsenic in groundwater

“…6 In general, for obvious reasons colorimetry is the method of choice for the eld detection of a species and with several visual kits reported in the literature and also available commercially, arsenic is no exception. 1,[6][7][8][9][10][11][12][13][14] Most of these kits are essentially based on the Gutzeit method developed more than a century ago. 15 The method employs (a) the conversion of arsenic in water to arsenic (AsH 3 ) gas with a reducing agent and (b) subsequently its reaction with mercury bromide (HgBr 2 ) to produce arsenic mercury bromide (As(HgBr) 3 ).…”

“…7 However, materials enabling an emphatic visual discrimination between water samples with different arsenic contents have largely been elusive. For example, a Mo based metal organic framework (Mo-MOF) reported by Vaid et al facilitates the spectrophotometric determination of As(V) down to 0.05 mg L À1 in water; however, its ability to visually differentiate water samples containing 0-50 mg L À1 arsenic appears doubtful from the color chart 8. It is a matter of further concern that authors have not addressed the interference from PO 4 3À ions in color development.…”

Spectroscopic and reactive characterization of mixed-metal Fe–Cr trimer nodes in metal–organic framework MIL-100

“…Not only do mixed-metal MOFs allow for combining functionalities unique to each of the individual metals, but they also offer opportunities for exploiting synergistic features resulting from interaction of different metals at length scales significantly smaller than those present in physical mixtures of monometallic MOFs. Mixed-metal MOFs have thus far been evaluated toward a variety of applications including gas storage/separation, [1][2][3] sensing, 4,5 and heterogeneous catalysis. [6][7][8] MIL-100 (Materials of Institut Lavoisier) 9 (Fig.…”