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A novel WAlN/WAlON/Al₂O₃ coating was successfully deposited on stainless steel (SS) substrate using reactive DC and RF magnetron sputtering. Excellent spectrally selective property with a high absorptance of 0.958 in the solar spectrum region and low emittance of 0.08 in the infrared region were achieved by tailoring the target power, deposition time and the reactive flow rates of N₂ and O₂. In the present solar selective coating, W layer acts as a back reflector and diffusion barrier, WAlN as the main absorber layer, WAlON as the semi-absorber layer, whereas the topmost Al₂O₃ layer works as an anti-reflecting layer. In reference to the thermal stability, the absorber deposited on SS substrates exhibited high solar selectivity (α/ε) of 0.920/0.11, when heat treated in air up to 500 °C for 2 hrs. Taken together, the present study demonstrated that the WAlN/WAlON/Al₂O₃-based selective absorbing coating with …