Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,...Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.展开更多
β-Ga_(2)O_(3)是一种具有超宽带隙、高临界击穿场强和优异的巴利加优值的半导体材料,近年来在电力电子与深紫外光电探测等领域展现出巨大的应用潜力。金属有机化学气相沉积(Metal-organic chemical vapor deposition,MOCVD)技术凭借其...β-Ga_(2)O_(3)是一种具有超宽带隙、高临界击穿场强和优异的巴利加优值的半导体材料,近年来在电力电子与深紫外光电探测等领域展现出巨大的应用潜力。金属有机化学气相沉积(Metal-organic chemical vapor deposition,MOCVD)技术凭借其高生长速率、精确的膜厚控制、优异的薄膜质量和大尺寸生长等优势,成为未来β-Ga_(2)O_(3)走向产业化的潜在方法,并已被广泛应用于β-Ga_(2)O_(3)的外延生长研究。本文对几种常见晶向的β-Ga_(2)O_(3) MOCVD同质外延生长的研究成果进行了概述,并在此基础上介绍了极具潜力的β-(Al_(x)Ga_(1-x))_(2)O_(3)的MOCVD外延生长研究现状。最后,总结了基于MOCVD技术的β-Ga_(2)O_(3)同质外延生长以及β-(Al_(x)Ga_(1-x))_(2)O_(3)生长过程中面临的主要问题,并对未来的发展进行了展望。展开更多
基金China Postdoctoral Science Foundation (2023M733451)Dalian Innovation Team in Key Areas(2020RT06)Engineering Research Center for Key Aromatic Compounds and LiaoNing Key Laboratory,Liaoning Provincial Natural Science Foundation (Doctoral Research Start-up Fund 2024-BSBA-37)。
文摘Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.
文摘β-Ga_(2)O_(3)是一种具有超宽带隙、高临界击穿场强和优异的巴利加优值的半导体材料,近年来在电力电子与深紫外光电探测等领域展现出巨大的应用潜力。金属有机化学气相沉积(Metal-organic chemical vapor deposition,MOCVD)技术凭借其高生长速率、精确的膜厚控制、优异的薄膜质量和大尺寸生长等优势,成为未来β-Ga_(2)O_(3)走向产业化的潜在方法,并已被广泛应用于β-Ga_(2)O_(3)的外延生长研究。本文对几种常见晶向的β-Ga_(2)O_(3) MOCVD同质外延生长的研究成果进行了概述,并在此基础上介绍了极具潜力的β-(Al_(x)Ga_(1-x))_(2)O_(3)的MOCVD外延生长研究现状。最后,总结了基于MOCVD技术的β-Ga_(2)O_(3)同质外延生长以及β-(Al_(x)Ga_(1-x))_(2)O_(3)生长过程中面临的主要问题,并对未来的发展进行了展望。