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Various rare earth oxide nanostructures were synthesized for the first time by dual-double pulsed gas feeding/pulsed laser deposition. The optically transparent and insulating nanostructures do not exhibit the standard columnar configuration of rare earth oxide thin films but rather dense structures and a significant chemical stoichiometry. More precisely, they exhibit single crystallographic low temperature phases with preferential textures, generally similar to that of the bulk used powder targets. For the cubic fluorine type CeO₂ and Ho₂O₃ films, an epitaxial growth is observed with a special feature noticed in the case of the Eu₂O₃ nanostructure. For this latter, localized and very large oriented crystallites embedded in disordered packed pyramidal crystallites are observed.

Using laser cladding technology, a Ni60A alloy cladding layer added with rare earth oxides CeO₂ and Cr₃C₂ was prepared on the surface of Cr12MoV die steel. Through scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) analyses, the influence of CeO₂ on the microstructure, hardness and wear resistance of Ni60A–Cr₃C₂ laser cladding layer was studied, and the mechanism of action of CeO₂ was discussed. The results show that in the laser cladding Ni60A–Cr₃C₂ coating, after adding CeO₂ powder, the cladding layer is well formed and the microstructure is significantly refined. As the addition of CeO₂ increases, the microhardness of the cladding layer increases first and then decreases. When the addition amount of CeO₂ is 2wt.%, the microhardness of the coating is the largest, which is 1107HV. As the content of CeO₂ continues to increase, the hardness decreases. As the content of CeO₂ in the cladding layer increases, the wear loss of the sample first decreases and then increases. When the mass fraction of CeO₂ is 1wt.%, the wear loss of the cladding layer is the least and the wear resistance is the best. The wear morphology of the Ni60A+Cr₃C₂ cladding layer without adding CeO₂ appears with a lot of abrasive debris, and the main mechanism is adhesive wear. When the addition amount of CeO₂ is 1wt.%, the wear mainly appears as furrow, which denotes abrasive wear.

One-step synthetic route has been developed for the preparation of Nd(OH)₃ nanorods in the presence of n-butylamine. The as-prepared sample is in hexagonal phase with good crystallinity, and made up of highly dispersed nanorods of 14–15 nm in diameter and up to 40–50 nm in length at 120°C for 24 h. Optical measurements show that these nanorods have intensive photoluminescence (PL) at room temperature and have the potential to become optical materials. Thermogravimetric analysis (TGA) of the Nd(OH)₃ nanorods reveals that the nanorods remain stable up to 220°C and decompose to the derived oxide of Nd₂O₃ at higher temperatures. The derived oxides show the promise active catalyst for the oxidation of carbon monoxide. In addition, this synthetic route has been developed for the synthesis of a series of other lanthanide hydroxides nanorods including Pr(OH)₃, Sm(OH)₃, Eu(OH)₃, Gd(OH)₃, Tb(OH)₃ and Dy(OH)₃, and their PL properties, thermostability and catalytic properties are investigated.