Photocatalytic hydrogen production using semiconductors is identified as one of the most promising routes for sustainable energy; however, it is challenging to harvest the full solar spectrum in a particulate photocatalyst for high activity. Herein, a hierarchical hollow black TiO2/MoS2/CdS tandem heterojunction photocatalyst, which allows broad‐spectrum absorption, thus delivering enhanced hydrogen evolution performance is designed and synthesized. The MoS2 nanosheets not only function as a cost‐effective cocatalyst but also act as a bridge to connect two light‐harvesting semiconductors into a tandem heterojunction where the CdS nanoparticles and black TiO2 spheres absorb UV and visible light on both sides efficiently, coupling with the MoS2 cocatalyst into a particulate photocatalyst system. Consequently, the photocatalytic hydrogen rate of the black TiO2/MoS2/CdS tandem heterojunction is as high as 179 µmol h−1 per 20 mg photocatalyst under visible‐light irradiation, which is almost 3 times higher than that of black TiO2/MoS2 heterojunctions (57.2 µmol h−1). Most importantly, the stability of CdS nanoparticles in the black TiO2/MoS2/CdS tandem heterojunction is greatly improved compared to MoS2/CdS because of the formation of tandem heterojunctions and the strong UV‐absorbing effect of black TiO2. Such a tandem architectural design provides new ways for synthesizing particulate photocatalysts with high efficiencies.

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Ti3+ self-doped black TiO2 nanotubes (TDBTNs) with mesoporous nanosheet architecture have been successfully synthesized by solvothermal method combined with ethylenediamine encircling strategy to protect mesoporous frameworks, then calcined at 600 °C under hydrogen atmosphere. In this case, ethylenediamine molecules play important roles on maintaining the mesoporous networks and inhibiting the phase transformation from anatase-torutile effectively. The as-prepared TDBTNs with mesoporous nanosheet architecture possess a relatively high specific surface area of ∼95 m2 g–1 and an average pore size of ∼15.6 nm. The reduced bandgap of ∼2.87 eV extends the photoresponse from ultroviolet to visible light region due to the Ti3+ self-doping. The solar-driven photocatalytic hydrogen evolution rate for TDBTNs is approximately 3.95 mmol h–1 g–1, which is much better (about four times) than that of the pristine one (∼0.94 mmol h–1 g–1). This improvement is attributed to the reduced bandgap increasing the utilization ratio of solar energy, the formed Ti3+ enhancing separation efficiency of photogenerated charge carriers, and the special one-dimensional mesoporous architecture offering more surface active sites.