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[EN] Thin films of ferromagnetic LTP-MnBi (Low Temperature Phase of MnBi) have been grown by magnetron sputtering onto quartz substrates. Two particular issues related to LTP-MnBi have been investigated: the strong influence of the growth temperature and the degradation of magnetic properties in time. The temperature dependence on the magnetic, morphological and microstructural properties has been investigated, evidencing drastic changes on the properties of MnBi with small temperature variations. By inducing a gradient of temperature during the growth, two well differentiated regions with different morphology and crystal structure have been observed in a MnBi film sample. On the other hand, aging experiments performed in a different LTP-MnBi sample has led to a notable decrease of 54% in the saturation magnetization after 6 days and a complete loss of ferromagnetic response after 4 months. ; The authors acknowledge the financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) through NEXMAG (M-era.Net Programme, Ref. No. PCIN-2015- 126), 3D-MAGNETOH (Ref. No. MAT2017-89960-R) and Ref. No. MAT2014-52402-C2-2-R, and from the Regional Government of Madrid through NANOMAGCOST project (Ref. P2018/NMT-4321).

Data of optical performance, thermal stability and ageing are given for solar selective coatings (SSC) based on a novel MoSi2-Si3N4 absorbing composite. SSC have been prepared as multilayer stacks formed by silver as metallic infrared reflector, a double layer composite and an antireflective layer (doi:10.1016/j.solmat.2016.04.001 [1]). Spectroscopic reflectance data corresponding to the optical performance of samples after moderate vacuum annealing at temperatures up to 600 °C and after ageing test of more than 200 h with several heating-cooling cycles are shown here ; This work has been supported by European Commission under HITECO Collaborative project contract No. 256830 from the FP7-ENERGY program and by the CSIC PIE project E201460E108, by the Spanish MINECO through contract MAT2012-37276-C03-01 and by the Madrid Regional Government through contract P2013/MIT-2740. E.C. acknowledges MINECO for the "Formación Posdoctoral (JdC)" program (FPDI-2013)