The
excessive presence of ammonia and ammonium in groundwater poses
potential hazards to human health and ecosystems; thus, accurate measurement
of the ammonia nitrogen concentration is very important. Herein, a
stable and highly luminescent decorated Tb-MOF was prepared by a hydrothermal
and substitution reaction. Under the optimized detection conditions,
the decorated Tb-MOF can detect ammonia nitrogen with an exceptional
fluorescence enhancement in a wide detection range. The detection
limit was determined to be 1.5514 × 10–2 μM
in the lower concentration range from 0 to 0.0021 M. In addition,
the as-prepared nanosensor also exhibited superior detection selectivity
and anti-interference with respect to ammonia nitrogen, and the detection
mechanism was investigated as the formation of an isoindole complex
from dialdehyde with ammonia nitrogen to induce the energy transfer
process. Furthermore, its practical ability was studied in groundwater
with a decorated Tb-MOF. The detection in actual groundwater samples
proves that this material can be used for practical applications.
Our research provides a new method for visual, rapid, and in situ
detection of ammonia nitrogen in groundwater.