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The construction of efficient semiconductor/cocatalyst heterojunction is a promising strategy to promote the photocatalytic H 2 -production efficiency from water reduction. Herein, a novel Cu 2 (OH) 2 CO 3 /Zn 0.5 Cd 0.5 S heterojunction composite with superior photocatalytic H 2 -generation activity and stability was prepared via a facile in situ synthetic route, in which Cu 2 (OH) 2 CO 3 served as cocatalyst stimulating the photocatalytic H 2 -evolution performance of Zn 0.5 Cd 0.5 S. The Cu 2 (OH) 2 CO 3 /Zn 0.5 Cd 0.5 S heterojunction photocatalyst containing 5 wt% of Cu 2 (OH) 2 CO 3 exhibited a prominent H 2 -evolution efficiency of 275.7 μmol h−1, which is superior to the noble metal Pt-modified Zn 0.5 Cd 0.5 S photocatalyst (237.3 μmol h−1) and much higher than bare Zn 0.5 Cd 0.5 S (90.8 μmol h−1). The active Cu+/Cu0 species generated during the photoreaction process is responsible for the prominent H 2 -production activity of the heterojunction photocatalyst, which plays triple roles in enhancing the photoactivity of Zn 0.5 Cd 0.5 S via accelerating the charge separation, decreasing the overpotential of H 2 -generation and improving the reduction ability of photoinduced electrons. Moreover, the formed Cu+/Cu0 species during photoreaction can be readily oxidized back to Cu 2 (OH) 2 CO 3 upon exposure to air, thus restores the photoactivity and therefore enables good reusability of the Cu 2 (OH) 2 CO 3 /Zn 0.5 Cd 0.5 S heterojunction photocatalysts. This work provides a new insight into the fabrication of Cu 2 (OH) 2 CO 3 -assisted heterojunction photocatalysts with the highly stable and efficient performances for solar-to-chemical energy conversion. Unlabelled Image • A novel binary Cu 2 (OH) 2 CO 3 /Zn 0.5 Cd 0.5 S composite was successfully synthesized. • The trifunctional roles of Cu 2 (OH) 2 CO 3 cocatalyst were discussed. • Mechanism of the enhanced photocatalytic activity was illuminated. [ABSTRACT FROM AUTHOR]

In this paper, novel TiO 2 /Bi 2 WO 6 heterojunction photocatalysts with hollow microsphere structures were successfully fabricated by a one-pot glucose-assisted hydrothermal route followed by the calcination at 450 °C. The photocatalytic activities of the as-prepared photocatalysts were evaluated on the degradation of rhodamine B (RhB) aqueous solution under visible light irradiation and the results indicated that the as-prepared TiO 2 /Bi 2 WO 6 composite exhibited higher photocatalytic activity than bare TiO 2 and Bi 2 WO 6 . In addition, the TiO 2 /Bi 2 WO 6 composite with TiO 2 loading of 20 wt.% showed the highest photocatalytic activity and retained the high photocatalytic performance after four recycles for the photodegradation of RhB, confirming its stability and practical usability. The enhanced photocatalytic activity of TiO 2 /Bi 2 WO 6 composite was attributed to well matched energy band positions of TiO 2 and Bi 2 WO 6 , which facilitated the efficient separation of photogenerated electron–hole pairs and thereby led to the increasing photocatalytic activity. On the basis of calculated energy band positions, the results of photoluminescence (PL) and active species trapping experiments, the mechanism of the obviously enhanced photocatalytic performance was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Direct Z-scheme Mn 0.5 Cd 0.5 S/CoTiO 3 heterojunction was designed. • Mechanism for the enhanced photoactivity over Mn 0.5 Cd 0.5 S/CoTiO 3 heterojunction discussed. • High ammonia production rate achieved over heterojunction, 5.1-fold higher than Mn 0.5 Cd 0.5 S. The exploration and design of highly efficient and robust photocatalysts composed of earth-abundant materials for ambient photocatalytic N 2 fixation to ammonia remains a significant challenge. Here, we have fabricated a stable and highly efficient direct Z-scheme Mn 0.5 Cd 0.5 S/CoTiO 3 heterostructure for N 2 fixation by depositing Mn 0.5 Cd 0.5 S nanoparticles on CoTiO 3 surface. Under ambient conditions, the optimized Mn 0.5 Cd 0.5 S/CoTiO 3 heterojunction achieved a significant NH 3 production rate of 121.9 μmol g-1h−1 without cocatalyst modification, representing a 5.1- and 5.9-fold increase over pristine Mn 0.5 Cd 0.5 S and CoTiO 3 , respectively, and also exceeding most previously reported photocatalytic systems. The significant improvement in ammonia production primarily results from the Z-scheme charge transfer path between the Mn 0.5 Cd 0.5 S and CoTiO 3 components, which enables effective separation of photoinduced carriers while maintaining their robust redox capacity, thus dramatically boosting ammonia generation performance. This research may provide new insights for advancing other alternative Z-scheme photocatalytic systems with remarkable stability and exceptional efficiency in N 2 fixation. [ABSTRACT FROM AUTHOR]