High-entropy alloy nanocrystals boosting photocatalytic hydrogen evolution coupled with selective oxidation of cinnamyl alcohol  

高熵合金纳米晶体促进光催化析氢耦合肉桂醇选择性氧化

作　　者：Xianglin Xiang Bei Cheng Bicheng Zhu Chuanjia Jiang Guijie Liang 项祥林;程蓓;朱必成;姜传佳;梁桂杰(昆明理工大学材料科学与工程学院,云南昆明650093;武汉理工大学材料复合新技术国家重点实验室,湖北武汉430070;中国地质大学(武汉)材料与化学学院太阳燃料实验室,湖北武汉430078;南开大学环境科学与工程学院,天津300350;湖北文理学院低维光电材料与器件湖北省重点实验室,湖北襄阳441053)

机构地区：[1]Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China [2]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,Hubei,China [3]Laboratory of Solar Fuel,Faculty of Materials Science and Chemistry,China University of Geosciences,Wuhan 430078,Hubei,China [4]College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China [5]Hubei Key Laboratory of Low Dimensional Arts and Science,Hubei University of Arts and Science,Xiangyang 441053,Hubei,China

出　　处：《Chinese Journal of Catalysis》2025年第1期326-335,共10页催化学报(英文)

基　　金：国家重点研发计划项目(2022YFB3803600);国家自然科学基金项目(22238009,22361142704,22261142666,22278324,52073223);湖北省自然科学基金项目(2022CFA001);中央高校基本科研业务费(63241632).

摘　　要：Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products.光催化可以利用太阳光实现产氢和可控有机转化的耦合反应,为全球面临的能源和重要工业原料短缺问题提供潜在解决方案.光催化剂的设计构筑是实现该技术的关键。硫化镉(CdS)量子点因其优异的可见光吸收能力、易于合成和形貌可控等优势而受到广泛关注.然而,由于缺乏高效的表面活性位点,其表面氧化还原反应进行缓慢,这严重制约了CdS量子点光催化剂的发展.当前,贵金属助催化剂(如Pt,Au,Ag等)在提高CdS量子点光催化产氢性能方面已展现出较大的潜力.然而,由于贵金属本身的稀缺性和高昂的价格使其应用受限.因此,在优化贵金属催化性能的基础上减少其用量显得尤其重要.与单一元素金属相比,合金化可以调节催化反应过程中反应底物或中间体在催化剂表面的吸附能以提高催化活性.与廉价金属形成合金不仅可以减少贵金属的使用量,还可以优化其光催化析氢性能.本文采用简单的溶剂热法合成了PtFeNiCoCu高合金(HEA)纳米晶助催化剂,并通过静电自组装法成功地将其与CdS量子点复合,构建了HEA/CdS复合材料,用于光催化产氢耦合肉桂醇的选择性氧化.由于HEA的黑色属性和HEA中的金属原子的d-d跃迁,复合样品表现出增强的可见至近红外光吸收.理论计算结果表明,相较于Pt纳米颗粒,高熵合金纳米晶的氢吸附自由能绝对值更接近零,表现出比纯的Pt纳米晶更高的催化活性.d带中心计算结果表明,HEA中的Pt原子是其主要析氢活性位点.飞秒瞬态吸收光谱表明,HEA可以显著促进CdS量子点中光生载流子的分离,这对于实现高效的光催化活性至关重要.因而,在最佳条件下,其光催化产氢速率为7.15 mmolg^(-1)h^(-1),比纯CdS量子点的光催化产氢速率高12倍.此外,原位漫反射傅立叶变换红外光谱和电子顺磁共振波谱结果表明,该体系中肉桂醇主要经过两个单电子反应步骤生成肉桂醛:(1)肉�

关 键 词：Artificial photosynthesis d-Band center Photocatalytic hydrogen evolution Quantum dots Value-added organic synthesis 

分 类 号：O62[理学—有机化学]