Eu(3+) doped ZnAl layered double hydroxides as calibrationless, fluorescent sensors for carbonate

The photoluminescence properties (PL) of Eu(3+) hosted in the hydroxide layers of layered double hydroxides (LDHs) enables calibrationless quantification of anions in the interlayers. The concept is demonstrated during the nitrate-to-carbonate ion exchange in Zn(2+)/Al(3+)/Eu(3+) LDHs and can be implemented as a remote optical sensor to detect intrusion of anions such as Cl(-) or CO(3)(2-).