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This contribution describes the preparation, coupled with detailed characterization, of Nb2O5 nanofibers and their application in lithium–sulfur batteries for the improvement of electrochemical performance. The utilization of reactive needle-less electrospinning allowed us to obtain, in a single step, amorphous pre-ceramic composite PAN/Nb2O5 fibers, which were transformed into porous ceramic Nb2O5 nanofibers via calcination. Thermogravimetric studies defined that calcination at 600 °C results in crystalline ceramic fibers without carbon residues. The fibrous morphology and mean diameter (614 ± 100 nm) of the ceramic nanofibers were analyzed via scanning and transmission electron microscopy. A surface area of 7.472 m2/g was determined through nitrogen adsorption measurements, while a combination of X-ray diffraction and Raman spectroscopy was used to show the crystallinity and composition of the fibers after calcination—single T-phase Nb2O5. Its performance in the cathode of lithium–sulfur batteries was defined through electrochemical tests, and the obtained results were compared to a similar blank electrode. The initial discharge capacity of 0.5 C reached a value of 570 mAh∙g−1, while the reversible capacity of 406 mAh∙g−1 was retained after 200 cycles, representing a capacity retention of 71.3%. The presence of Nb2O5 nanofibers in the carbon cathode inhibits the shuttle effect through polysulphide confinement, which originates from porosity and chemical trapping.

Lanthanide Metal–Organic Frameworks (LnMOFs), in recent years, have developed into an interesting subclass of MOFs. While the number of published papers, in particular, were dedicated to their synthesis and functional properties, along with the application mechanisms of MOFs, only a few of them have been focused on LnMOFs thin films independently. LnMOFs have become interesting thanks to their outstanding properties, for example, excellent structural flexibility, tunable pore size, surface area, functionality, and good chemical stability. Significant progress over the past two decades in the preparation of MOF films has been achieved, especially towards the development of green, or at least greener, synthesis approaches. We begin with insight into various types of MOFs and summarize recent achievements in the production of LnMOF films, along with various film preparation approaches. Afterward, we briefly discuss the applications of luminescence features of lanthanide ions in films and their potential as white-light source materials. We also covered films based on Eu, Tb, and Gd with particular accents on different design approaches. Moreover, specifically, luminescent features applied for sensing temperature, a variety of ions, gases, and biomolecules are highlighted. The review ends with a comprehensive conclusion about the state-of-art-potential of LnMOFs together with an outlook on the future of LnMOF films in future technologies.