Influence of solvents on properties of solar selective coatings obtained by spray pyrolysis

Developments in the synthesis of flat plate solar selective absorber materials via sol–gel methods: A review

“…Dudita [86] has synthesized the copper oxide-nickel oxide composite selective absorber on a copper substrate by the robotic spray pyrolysis method at 330 °C. The solutions used were a mixture of nickel acetate and copper acetate in water-ethanol solution based on the previously optimized conditions [87].…”

“…The best selectivity (36.4) was obtained from film with highest roughness (precursors with 40% ethanol). They proposed two parallel mechanisms of high selectivity: intrinsic absorption and multiple reflections generated when absorbers with controlled roughness are deposited [86].…”

Spectrally Solar Selective Coatings for Colored Flat Plate Solar Thermal Collectors

“…A broad range of these materials are mainly deposited using wet chemical techniques: electrodeposition, anodization, sol-gel, solution growth, spray pyrolysis etc. [2,9,11,[13][14][15][16][17][18][19]. Spray pyrolysis deposition (SPD) has the advantage of low complexity, good reproducibility, up-scalable applications and, last but not least, low cost.…”

“…Most of black solar absorber coatings are formed by cermets composed of metals such as Mo, Ni, Cu, Fe, Cr, Au or Pt embedded in ceramic matrixes of (a) metal oxides: Al 2 O 3 [1,11,14,[20][21][22][23], NiO [18,24], CrNiO x [14,25], Cu x O [19,[26][27][28][29] and SiO 2 [1], (b) oxynitrides: NbAlON [28], CrON [12], or (c) nitrides: NbAlN [28], Si 3 N [3], CrMoN [12].…”

“…By controlling the film morphology using maleic anhydride copolymers as additives into the precursors' solution, solar absorber with good selectivity (19) were obtained. The high selectivity values (S > 30) of the optimized CuO x -NiO x composite coatings, obtained on Cu substrate using nickel and copper acetate, dissolved in mixed solvents with various water: ethanol ratios, were explained based on two parallel mechanisms: intrinsic absorption and multiple reflections generated when absorbers with controlled roughness are deposited [19].…”