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利用人工光合成将太阳能转化为化学燃料是太阳能利用的重要途径,具有广阔的应用前景,其中,太阳能光催化分解水制氢是最为关键的反应之一.但是,大多数半导体光催化材料面临着光生电荷分离困难和表面催化反应速率慢等挑战.本文以具有可见光响应的半导体光催化剂Cd0.9Zn0.1S(CZS)纳米棒为研究模型,利用水热法成功在其表面上均匀地组装氧化钴物种(CoOx),构建了多级异质结构CZS@CoOx.扫描电子显微镜和透射电子显微镜显示,表面组装的CoOx物种均匀地覆盖在CZS纳米棒的整个表面上,形成了有序的CZS@CoOx核壳多级异质结构.高分辨率透射电子显微镜进一步确认了氧化钴晶格间距与六方CZS的(002)晶面高度匹配,利于光生电荷在界面的分离和转移.稳态荧光光谱测试表明,与物理混合的样本相比,CZS@CoOx多级异质结构表现出明显降低的荧光强度,说明多级异质结构能有效促进光生电子-空穴对的分离.时间分辨荧光光谱结果显示,CZS@CoOx多级异质结构的平均光生电荷寿命明显增长,进一步确认了多级异质结构对光生电荷分离的作用.此外,电化学开路电位测量显示,增强的开路电压响应归因于多级异质结构CZS@CoOx中致密的界面接触.电化学阻抗谱进一步确认,与没有形成致密界面结构的CZS-CoOx和CZS/CoOx相比,多级异质结构CZS@CoOx的电荷转移电阻大幅度降低,从而确保了更快的界面电荷分离和转移.最后对CZS@CoOx多级异质结构的光催化产氢活性进行了评价,发现其光催化产氢的性能远高于贵金属Pt/CZS光催化剂;进一步测量了CZS@CoOx的表观量子效率,在420 nm处光催化产氢的表观量子效率为20％.此外,在多级异质结构CZS@CoOx上进一步引入Pt助催化剂,可将表观量子效率进一步提升至37％.本文报道的这一简易可行的表面组装构建多级异质结构的策略有望在太阳能光催化领域发挥重要作用.“,”Although photocatalytic water splitting has excellent potential for converting solar energy into chemical energy, the challenging charge separation process and sluggish surface catalytic reactions significantly limit progress in solar energy conversion using semiconductor photocatalysts. Herein, we demonstrate a feasible strategy involving the surface assembly of cobalt oxide species (CoOx) on a visible-light-responsive Cd0.9Zn0.1S (CZS) photocatalyst to fabricate a hierarchical CZS@CoOx het-erostructure. The unique hierarchical structure effectively accelerates the directional transfer of photogenerated charges, reducing charge recombination through the smooth interfacial hetero-junction between CZS and CoOx, as evidenced by photoluminescence (PL) spectroscopy and various electrochemical characterizations. The surface cobalt species on the CZS material also act as effi-cient cocatalysts for photocatalytic hydrogen production, with activity even higher than that of noble metals. The well-defined CZS@CoOx heterostructure not only enhances the interfacial separa-tion of photoinduced charges, but also improves surface catalytic reactions. This leads to superior photocatalytic performances, with an apparent quantum efficiency of 20％ at 420 nm for visi-ble-light-driven hydrogen generation, which is one of the highest quantum efficiencies measured among noble-metal-free photocatalysts. Our work presents a potential pathway for controlling complex charge separation and catalytic reaction processes in photocatalysis, guiding the practical development of artificial photocatalysts for successful transformation of solar to chemical energy.