With the development of new materials and technology,high entropy alloy(HEA)nitride films have attracted much attention of researchers due to their excellent optical properties and mechanical properties.Herein,a novel...With the development of new materials and technology,high entropy alloy(HEA)nitride films have attracted much attention of researchers due to their excellent optical properties and mechanical properties.Herein,a novel SS/NbMoTaWN(HEAN)/NbMoTaWON(HEAON)/SiO_(2) coatings are prepared,which shows a high spectral selectivity of a/ε=0.944/0.12.The preparation and optimization of the coating are studied by combining experiments with ellipsometric program and CODE software.High temperature thermal stability test is performed in depth,which proves that the coating could bear 400℃ in air for 2 h,and 600℃for 2 h in vacuum.Long-term thermal stability researches indicate that the SSACs still keep good optical properties(a=0.902,ε=0.106)even after annealing at 600℃ for 100 h.The failure mechanism is analyzed by XRD and Raman spectra.In addition,neutral salt spray test is performed to investigate the anti-corrosion ability,which indicates the coating has a good optical performance after soaking in 3.5 wt%NaCl solution for 30 days.Obviously,this work provides a new strategy to construct solar absorber coatings based on NbMoTaW high entropy alloy.展开更多
Transition metal nitrides(TMNs)have gained widespread application in protecting structural components due to their high strength and hardness.However,TMNs still have the challenge of structural instability and mechani...Transition metal nitrides(TMNs)have gained widespread application in protecting structural components due to their high strength and hardness.However,TMNs still have the challenge of structural instability and mechanical deterioration caused by oxidation under harsh high temperature conditions.Herein,we present a strategy combining component regulation with high-entropy engineering to develop an advanced high-temperature Al-containing high-entropy nitrides(HENs)material.To prevent the phase decomposition of AlN within the(NbMoTaWAl)N,theoretical simulations were employed to determine a critical atomic percent of 25.0%Al for maintaining the stability of the high-entropy structure.Ensuing experimental synthesis creates three NbeMoeTaeWeAleN films with varying Al content:a high-entropy film with 0.0%Al(HEN),a high-entropy film with 21.2%Al(HEN-Al),and an amorphous transition metal nitride film with 30.2%Al(a-TMN-Al),validating key high-entropy engineering benchmarks.It is found that the unique HEN-Al film exhibits excellent oxidation resistance and hightemperature hardness,attributed to the uniform distribution of Al atoms in the robust high-entropy structure,which creates conditions for forming a dense and continuous Al_(2)O_(3) barrier layer,effectively hindering the diffusion of oxygen into the film interior.This study provides new insights to develop a new generation of high-temperature protective materials.展开更多
基金This workwas financially supported by the regional key projects of science and technology service network program of Chinese Academy of Sciences(KFJ-STS-QYZD-139)the Youth Innovation Promotion Association CAS(2018455)the Major Science and Technology Projects of Gansu Province(20ZD7GF011).
文摘With the development of new materials and technology,high entropy alloy(HEA)nitride films have attracted much attention of researchers due to their excellent optical properties and mechanical properties.Herein,a novel SS/NbMoTaWN(HEAN)/NbMoTaWON(HEAON)/SiO_(2) coatings are prepared,which shows a high spectral selectivity of a/ε=0.944/0.12.The preparation and optimization of the coating are studied by combining experiments with ellipsometric program and CODE software.High temperature thermal stability test is performed in depth,which proves that the coating could bear 400℃ in air for 2 h,and 600℃for 2 h in vacuum.Long-term thermal stability researches indicate that the SSACs still keep good optical properties(a=0.902,ε=0.106)even after annealing at 600℃ for 100 h.The failure mechanism is analyzed by XRD and Raman spectra.In addition,neutral salt spray test is performed to investigate the anti-corrosion ability,which indicates the coating has a good optical performance after soaking in 3.5 wt%NaCl solution for 30 days.Obviously,this work provides a new strategy to construct solar absorber coatings based on NbMoTaW high entropy alloy.
基金supported by the National Natural Science Foundation of China(Grant Nos.52322206,51972139)the Science and Technology Development Program of Jilin province(Grant No.20210101062JC)+1 种基金funded by the National Key R&D Program of China(2023YFF0716800)the High-Performance Computing Center of Jilin University,China.
文摘Transition metal nitrides(TMNs)have gained widespread application in protecting structural components due to their high strength and hardness.However,TMNs still have the challenge of structural instability and mechanical deterioration caused by oxidation under harsh high temperature conditions.Herein,we present a strategy combining component regulation with high-entropy engineering to develop an advanced high-temperature Al-containing high-entropy nitrides(HENs)material.To prevent the phase decomposition of AlN within the(NbMoTaWAl)N,theoretical simulations were employed to determine a critical atomic percent of 25.0%Al for maintaining the stability of the high-entropy structure.Ensuing experimental synthesis creates three NbeMoeTaeWeAleN films with varying Al content:a high-entropy film with 0.0%Al(HEN),a high-entropy film with 21.2%Al(HEN-Al),and an amorphous transition metal nitride film with 30.2%Al(a-TMN-Al),validating key high-entropy engineering benchmarks.It is found that the unique HEN-Al film exhibits excellent oxidation resistance and hightemperature hardness,attributed to the uniform distribution of Al atoms in the robust high-entropy structure,which creates conditions for forming a dense and continuous Al_(2)O_(3) barrier layer,effectively hindering the diffusion of oxygen into the film interior.This study provides new insights to develop a new generation of high-temperature protective materials.
