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It is well known that the upconversion luminescence from lanthanide metal–organic frameworks (Ln-MOFs) is difficult to achieve, and thus, there are few reports on dual luminescence-based MOFs. Here, dual-mode light-emitting Ln-MOFs are synthesized using a low-cost hydrothermal method. Our results show that the obtained Ln-MOFs not only have high thermal stability (up to 420°) but also are stable in deionized water. The dual-mode up- and downconversion luminescence is simultaneously observed from Er–Eu-MOFs. The temperature-dependent fluorescence decay time is calculated to be ranging from 0.46 to 0.36 ms for temperatures from 100 to 300 K. We suggested that this phenomenon was because the number of phonons participating in the MOF matrix increases with temperature during the luminescence process, and the phonons interact with the electrons in the material. The values of the J–O parameters calculated from the emission spectra indicated that the symmetry around Eu3+ ions in Eu-MOF is the highest, which was also higher than that of Er–Eu-MOF. To explore the potential applications of Eu-MOFs in white light-emitting diodes (LEDs), red emission from Eu-MOFs was combined with blue, green, and yellow emissions from metal halide perovskites to achieve white light emission. White light with excellent color quality and vision performance was obtained. These findings demonstrate that Ln-MOFs are potentially successful materials for applications in white LEDs.

Multifunctional nanomaterials for bioprobe and drug carrier have drawn great attention for their applications in the early monitoring the progression and treatment of cancers. In this work, we have developed new multifunctional water-soluble NaLnF4@MOF-Ln nanocomposites with dual-mode luminescence, which is based on stokes luminescent mesoporous lanthanide metal–organic frameworks (MOFs-Y:Eu3+) and anti-stokes luminescent NaYF4:Tm3+/Yb3+ nanoparticles. The fluorescence mechanism and dynamics are investigated and the applications of these nanocomposites as bioprobes and drug carriers in the cancer imaging and treatment are explored. Our results demonstrate that these nanocomposites with the excellent two-color emission show great potential in drug delivery, cancer cell imaging, and treatment, which are attributed to the unique spatial structure and good biocompatibility characteristics of NaLnF4@MOF-Ln nanocomposites.

The use of solar energy to convert CO2 into chemical fuels not only can create renewable energy but also can alleviate the greenhouse effect. In this work, MgO/LaFeO3 : Er3+ composites were prepared, and their photocatalytic CO2 reduction capability was tested under visible‐light irradiation. The MgO/LaFeO3 : Er3+ composites displayed improved charge carrier separation efficiency, higher CO2 adsorption capacity, and increased photoactivities for photocatalytic CO2 reduction to CO and CH4 (71.52 μmol g−1 h−1 and 5.54 μmol g−1 h−1, respectively). As a comparison, the production rates of CO and CH4 are 29.36 μmol g−1 h−1 (CO) and 4.13 μmol g−1 h−1, respectively for pure LaFeO3. The enhanced photoactivities are attributed to the increased electron‐hole separation rate resulting from the Er3+ doping and improved CO2 adsorption capacity by MgO coupling. This work thus identifies a novel approach towards highly efficient photocatalysts for CO2 reduction.

Synthesis routes of 6-aminopyridine-3-boronic acid-functionalized magnetic nanoparticles assisted by polyethylenimine (Fe3O4@PEI@PYBA).