Surface-textured Mo thin film is fabricated by magnetron sputtering through the adjustment of deposition parameters, which exhibits a high absorptance of 0.80 and a low emittance of 0.09. The single-layer Mo deposited on stainless steel (SS) is characterized by x-ray diffraction (XRD), ultra-high resolution scanning electron microscope, atomic force microscope and optical measurement. The controlled surface roughness combined with larger aspect ratio contributes much to the high absorptance and low emittance. Based on the SS/Mo coating, a spectrally selective coating (SS/Mo/Al2O3) is designed and fabricated. The coating shows an amorphous structure and exhibits an absorptance of 0.90 and an emittance of 0.08. Tauc-Lorentz and Drude free-electron models are used to modeling the optical properties of Al2O3 and Mo layers by phase-modulated spectroscopic ellipsometry.

•The SS/TiC/Al2O3 solar absorber coating has been simulated by CODE software.•The coating exhibits a good anti-corrosion performance.•The coating exhibits a good thermal stability at 500 °C for 100 h in vacuum.This work is a continuation of earlier work where TiC/Al2O3 spectrally selective solar absorbers were deposited onto stainless steel (SS). In this study, the optical simulation, corrosion behavior and long term thermal stability are investigated in detail. A series of TiC and Al2O3 single layers are fabricated by magnetron sputtering using the same deposition parameters as described in the previous work. The optical constants and thicknesses of glass, stainless steel, TiC and Al2O3 layers are obtained by CODE software using the suitable dielectric function model. Then, the structure model of SS/TiC/Al2O3 is constructed and the reflectance spectra of the SS/TiC/Al2O3 solar absorber is successfully simulated using CODE software. The anti-corrosion performance of SS/TiC/Al2O3 solar absorbers is evaluated through electrochemical potentiodynamic polarization measurement and salt spray test. The SS/TiC/Al2O3 solar absorbers have a good thermal stability in vacuum at 500 °C for 100 h. Raman analysis indicates that the increased sp2 bonds of the coating is the main reason for the degradation of the optical properties.

•The tandem SS/TiC/Al2O3 solar absorber exhibits a high absorptance of 0.92 and a low emittance of 0.13 (82 °C).•XPS and Raman analysis confirm the existance of amorphous carbon with sp2 and sp3 bonds.•During the sintering process, the C atoms gradually diffuse up to the surface and form graphitic layer.•The tandem SS/TiC/Al2O3 solar absorber shows good thermal stability in vacuum.A new spectrally selective solar absorber coating of TiC/Al2O3 is prepared on stainless steel substrate using a magnetron sputtering method. The new coating exhibits a high absorptance of 0.92 and a low emittance of 0.13 (82 °C). The tandem absorber is characterized using ultra-high resolution scanning electron microscope, UV–vis–NIR spectrophotometer, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The formation of amorphous carbon is due to the dissociation of TiC layer deposited under high substrate temperature (300 °C). The diffused carbon at 600–800 °C with mixed sp2 and sp3 bonds is further demonstrated by XPS and Raman spectra. With an increase in annealing temperature, the surface structure becomes more graphitic. The tandem absorber is stable in vacuum up to 650 °C for 2 h, indicating its importance for high temperature solar selective applications.

•Cu1.5Mn1.5O4-based CSS coating is achieved after only one dipping/annealing cycle.•Cu1.5Mn1.5O4 coating is obtained as the annealing temperature reaches to 450 °C.•Cu1.5Mn1.5O4 coating exhibits optical parameter: αs = 0.876 and ε100 = 0.057.•Cu1.5Mn1.5O4 coating shows the excellent stability in low to mid temperature region.Cu1.5Mn1.5O4-based ceramic spectrally selective (CSS) coating was deposited on aluminum substrate using a sol–gel dip-coating method. The citric acid introduced in the precursor system lowered the required calcining temperature of crystalline Cu1.5Mn1.5O4. X-Ray diffraction (XRD) peaks of coatings annealed above 450 °C were found to coincide exactly with that of crystalline Cu1.5Mn1.5O4 in JCPDS database. By optimizing the withdrawal rate and calcining temperature, coating with spectral selectivity as good as αs = 0.876 and ε100 = 0.057 was achieved after only one dipping/annealing cycle. Subjected to an accelerated ageing test at 259 °C, the obtained CSS coating showed an excellent thermally durability with the performance criterion (PC) values below 0.05.

A tandem layer structured SS/TiC–ZrC/Al2O3 coating has been prepared by magnetron sputtering as a high temperature spectrally selective solar absorber. The coating consists of two layers; a TiC–ZrC layer and an Al2O3 layer. TiC and ZrC ceramics show inherent spectral selectivity, which is used to design spectrally selective solar absorbers. A co-sputtering technique was used to fabricate the absorptance layer (TiC–ZrC). The coating exhibits a high absorbance of 0.92 and a low emittance of 0.11, as well as good thermal stability with a selectivity of 0.92/0.13 even after annealing at 700 °C for 100 h under vacuum. The SS/TiC–ZrC/Al2O3 coating also shows good thermal stability at 400 °C for 5 h in air. The surface morphology, composition, structure and optical properties of the coating were characterized using SEM, XPS, XRD, Raman spectroscopy, UV-vis-NIR spectrophotometry and Fourier transform infrared spectroscopy. Benefiting from these advantageous features, the as-deposited SS/TiC–ZrC/Al2O3 coating can be a good candidate for concentrated solar power applications.

Herein, non-toxic, ample, and cheap water served as the solvent to dissolve Cu and Mn nitrate, chelating agent, and wetting agent, where a long-term stable sol solution could be easily obtained. The single layer solar absorber film derived from the above precursor has been successfully deposited on a stainless steel substrate via a facile and low-cost sol–gel dip-coating method. A spinel Cu1.5Mn1.5O4 phase for the single layer thin film could be achieved at the annealing temperature of 450 °C for 1 h. The effect of annealing temperature on the surface structure and optical properties of the thin film was systematically studied. The results revealed that the film thickness, integration of impurities, and surface texture (crystallinity, nanoporosity, and roughness) coordinately influenced solar absorptance and thermal emittance of the thin film. A Cu1.5Mn1.5O4 single layer thin film annealed at 500 °C exhibited excellent solar absorptance (αs = 0.914) and thermal emittance (ε100 = 0.125). Furthermore, the single layer spinel thin film also showed benign thermal stability at the corresponding working temperature. Consequently, it could be used as a promising candidate for solar absorber thin films and safely applied in low-to-mid temperature regions.

•Al2O3-WC nanocomposite ceramic solar absorber coating is successfully fabricated.•The nanocomposite ceramic solar absorber coating exhibits a high absorptance of 0.94 and a low emittance of 0.08.•The nanocomposite ceramic solar absorber coating exhibits a good thermal stability at 600 °C.•The reflectance spectra is successfully modelled by a commercial optical programme.Traditional metal-dielectric composite coating has found important application in spectrally selective solar absorbers. However, fine metal particles can easily diffuse, congregate, or be oxidized at high temperature, which causes deterioration in the optical properties. In this work, we report a new spectrally selective solar absorber coating, composed of low Al2O3 ceramic volume fraction (Al2O3(L)-WC) layer, high Al2O3 ceramic volume fraction (Al2O3(H)-WC layer) and Al2O3 antireflection layer. The features of our work are: 1) compared with the metal-dielectric composites concept, Al2O3-WC nanocomposite ceramic successfully achieves the all-ceramic concept, which exhibits a high solar absorptance of 0.94 and a low thermal emittance of 0.08, 2) Al2O3 and WC act as filler material and host material, respectively, which are different from traditional concept, 3) Al2O3-WC nanocomposite ceramic solar absorber coating exhibits good thermal stability at 600 °C. In addition, the solar absorber coating is successfully modelled by a commercial optical simulation programme, the result of which agrees with the experimental results.

•Aqueous solution chemical method to prepare single layer Cu1.5Mn1.5O4 spinel films.•Only one dipping/annealing cycle is employed to fabricate spinel films.•Cu1.5Mn1.5O4 spinel phase can be obtained at the annealing temperature of 500 °C.•Single layer films exhibit αs=0.906–0.915 and ε100=0.146–0.172.Spinel Cu1.5Mn1.5O4 thin films were fabricated by one step sol-gel dip-coating method using aqueous solution. The effect of deposition parameters on thickness, surface feature, and optical property of thin films was systematically studied. The results revealed that the increased withdrawal speeds and high concentration of metal ions in precursor were conducive to obtaining thicker films which exhibited excellent solar absorptance. Furthermore, the surface feature derived from the different concentrations of metal ions had a significant effect on optical behavior of the thin film. Consequently, excellent spectral selectivity of the thin film would be achieved by tuning those deposition parameters.

A new kind of thiazole-containing unsymmetrical ortho-diamine monomer, 2-amino-5-[4-(2′-aminophenoxy)phenyl]-thiazole (o-AAPPT), was synthesized by four steps, using 4-hydroxyacetophenone as starting material. A novel thiazole-containing polyimide was prepared from the resulting diamine o-AAPPT with BTDA via a conventional one-step method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal and thermo-oxidative stability.A new kind of thiazole-containing unsymmetrical ortho-diamine monomer and corresponding novel polyimide were synthesized. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal and thermo-oxidative stability.

Potato root water (PRW) contains ∼1.5% protein. In this study, expanded bed adsorption (EBA) chromatography with Amberlite XAD7HP resin adsorbent was used to isolate native protein from crude PRW. The optimal pH and ionic strength for potato protein binding onto Amberlite XAD7HP were 5.0 and 20 mmol/L. The EBA-refined proteins were dried by vacuum freeze drying and spray drying at varying outlet temperatures. Results indicated that low temperature spray drying was the most cost effective method with respect to retaining protease inhibitor activities. The dried protein concentrates appeared bright yellow or dark reddish brown, with a total glycoalkaloid content of ∼170 μg/g. The protease inhibitor activity was ∼400 mg/g and 11 ∼ 12 mg/g for trypsin inhibition and chymotrypsin inhibition, respectively. The results presented here suggest that EBA using Amberlite XAD7HP as the adsorbent is a feasible strategy for the direct adsorption of native protein from crude PRW.

•The SS/TiC-WC/Al2O3 solar absorber coating has been prepared.•The coating exhibits a high absorptance of 0.92 and a low emittance of 0.10.•The coating is investigated by chromaticity study.•The coating exhibits an good thermal stability at 500 °C for 100 h in vacuum.A new spectrally selective solar absorber coating of TiC-WC/Al2O3 tandem layer is designed and prepared on stainless steel (SS) substrate by magnetron sputtering. The coating consists of an absorptance layer (TiC-WC) and an antireflectance layer (Al2O3) from substrate to top. The new SS/TiC-WC/Al2O3 coating exhibits excellent selective absorbing properties with a high solar absorptance of 0.92 and a low thermal emittance of 0.11. The SS/TiC-WC/Al2O3 coating presents a purple color, which is further investigated by chromaticity study. The thermal stability of the coating is evaluated and characterized by SEM, XRD, UV–vis–NIR spectrophotometer, Fourier transform infrared spectroscopy, and Raman spectroscopy. Experimental results indicate that the coating is highly stable in vacuum at 500 °C for 100 h with a good solar selectivity of 0.92/0.11.