Table 4.

Limits of detection (LOD) of nanocrystalline europium(III) terephthalate tetrahydrate 3 and previously reported materials for Cu²⁺, Cr ³⁺ and Fe³⁺ ions.

Sensing Material	Method	Target Contaminant	LOD	Ref.
Eu2(bdc)3·4H2O	luminescent	Cu2+	1 μM	Current work
Tb(BTC)(H2O)	luminescent	Cu2+	10 μM	[2]
CDs@Eu-DPA MOFs	luminescent	Cu2+	26.3 nM	[3,43]
[Eu(PDC)1.5(DMF)]·(DMF)0.5(H2O)0.5	luminescent	Cu2+	10 mM	[7,44]
Eu2(FMA)2(OX)(H2O)4·4H2O	luminescent	Cu2+	100 μM	[7,45]
[Eu4(BPT)4(DMF)2(H2O)8]	luminescent	Cu2+	10 μM	[7,46]
[Tb3(L)2(HCOO)(H2O)5]·DMF·4H2O	luminescent	Cu2+	100 μM	[7,47]
[Eu(ox)2(H2O)](Me2NH2)(H2O)3	luminescent	Cu2+	10 μM	[10,48]
Zr6(O)8(OH2)8(tpdc)4	luminescent	Cu2+	1 μM	[10,49]
PCN-222-Pd(II)	luminescent	Cu2+	50 nM	[10,50]
Me2NH2@MOF-1	electrochemical	Cu2+	10 pM	[3,51]
Eu2(bdc)3 nanoparticles	luminescent	Fe3+	30 μM	Current work
[Me2NH2][In(abtc)]·solvents	luminescent	Fe3+	34.5 μM	[52]
[LnK(BPDSDC)(DMF)(H2O)]·x(solvent)	luminescent	Fe3+	10 μM	[10,53]
[Eu(BTPCA)(H2O)]·2DMF·3H2O	luminescent	Fe3+	10 μM	[7,54]
[Eu(HL)(H2O)2]n·2H2O	luminescent	Fe3+	1 μM	[7,55]
EuL	luminescent	Fe3+	100 μM	[7,56]
[H2NMe2]3[Tb(DPA)3]	luminescent	Fe3+	10 μM	[7,57]
Eu (4′-(4-carboxyphenyl)-2,2′: 6′,2″-terpyridine)3	luminescent	Fe3+	100 μM	[7,58]
[H(H2O)8][DyZn4(imdc)4(im)4]	luminescent	Fe3+	1 mM	[7,59]
Eu3+@Ga2(OH)4(C9O6H4)	luminescent	Fe3+	0.28 μM	[7,60]
nTbL	luminescent	Fe3+	10 μM	[7,61]
[Eu(atpt)1.5(phen)(H2O)]n	luminescent	Fe3+	500 μM	[7,62]
[(CH3)2NH2] ·[Tb(bptc)]·xS	luminescent	Fe3+	10 μM	[7,63]
Tb-BTB	luminescent	Fe3+	10 μM	[7,64]
[Eu3(BDC)4.5(H2O)(DMF)2]	luminescent	Fe3+	1 μM	[7,65]
[Cd(L)(BPDC)]·2H2O	luminescent	Fe3+	2 μM	[8,66]
[Cd(L)(SDBA)(H2O)]∙0.5H2O	luminescent	Fe3+	2 μM	[8,66]
[Zn5(hfipbb)4(trz)2(H2O)2]	luminescent	Fe3+	10 μM	[8,67]
[Eu(Hpzbc)2(NO3)]·H2O	luminescent	Fe3+	10 μM	[8,68]
[Eu(L)(H2O)2]·NMP·H2O	luminescent	Fe3+	100 nM	[8,69]
[Tb(L1)1.5(H2O)]·3H2O	luminescent	Fe3+	10 μM	[10,70]
Bisdiene macrocycle	luminescent	Fe3+	0.58 μM	[71]
2-(cyclohexylamino)-3-phenyl-4Hfuro [3,2-c]chromen-4-one	luminescent	Fe3+	1.73 μM	[72]
[Me2NH2][In(abtc)]·solvents	luminescent	Fe3+	34.5 μM	[53]
PPCOT/NiFe2O4/C-SWCNT	electrochemical	Fe3+	100 pM	[73]
Eu2(bdc)3 nanoparticles	luminescent	Cr3+	30 μM	Current work
Tb(BTC)(H2O)	luminescent	Cr3+	10 μM	[2]
[TbK(BPDSDC)(DMF)(H2O)2]			10 μM	[8,74]
[Eu2L3(DMF)3]·2DMF·5H2O	luminescent	Cr3+	75.2 nM	[75]
ATNA deriviative	electrochemical	Cr3+	130 pM	[76]