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In this study, a simple method was designed to prepare ordered mesoporous carbons embedded with molybdenum without any extreme conditions. We prepared three different ordered molybdenum carbide materials with mesoporous structures to explore the influence of the structure of molybdenum‐based materials on the HER catalytic efficiency. The ordered mesoporous molybdenum carbide catalysts (CMK‐3‐MoCx, fCMK‐3‐MoCx, CMK‐8‐MoCx) were characterized by SEM, TEM, XRD, nitrogen adsorption‐desorption and XPS. The HER is catalyzed efficiently on the three electrocatalysts, fCMK‐3‐MoCx shows the best HER electro‐catalytic performance with a small onset potential of −0.06 V vs. RHE, a low tafel slope of 66 mV dec−1 and a small over‐potential value of 89 mV at 10 mA cm−2. This excellent performance on HER is due to its high specific surface area and highly ordered mesoporous structure that resulted in excellent proton transport efficiency and high electron transfer rate. Our results provide a new research direction for the application of flat ordered mesoporous structures in catalysis. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid nano-material has a significant potential for enhancing the charge separation efficiency of photocatalyst. However, it remains an important issue to controllable synthesis new hybrid system with unique structure and earth-abundant materials for boosting photocatalytic hydrogen revolution. We report a facile one-step hydrothermal strategy to fabricate a novel Titania/β-cyclodextrin (TiO 2 /β-CD) organic-inorganic hybrid nano-material with an alveolate structure. In this hybrid system, β-CD not only played a critical role in alveolate structure formation, but also served as a bridge connecting target molecular and active sites on the TiO 2 surface to facilitate the separation and transfer of the photoexcited electrons with prolonged lifetime. As a result, this alveolate TiO 2 /β-CD composite exhibited outstanding photocatalytic activity and a H 2 evolution rate of 725 μmol/g·h was achieved over TiO 2 /β-CD which was 14 times of bare TiO 2 under simulated sunlight. This work paves a way for controllable synthesis of novel organic-inorganic hybrid nano-material with distinct structure for efficient photocatalysis. Image 1 • A novel alveolate organic-inorganic hybrid has been successfully prepared. • The hybrid composite exhibited outstanding photocatalytic activity. • The H 2 evolution rate of TiO 2 /β-CD has a good durability. • This work paves a way for controllable synthesis of organic-inorganic TiO 2. • Limited reports on the photocatalytic water splitting of the TiO 2 /β-CD. [ABSTRACT FROM AUTHOR]

In this study, the optimized CdS/Ni-MOF photocatalyst with considerable activity and good stability for H 2 evolution was obtained by in-situ growth of CdS nanoparticles on the surface of Ni-MOF. Ni-MOF as an ideal support hinders the aggregation of CdS during the synthesis period. As a noble-metal-free catalyst, the obtained CdS/Ni-MOF composite having an optimal CdS loading of 40 wt% exhibits a remarkable H 2 production rate of 2508 μmol/g/h under visible light, which is about eight times higher than that of single CdS. The CdS/Ni-MOF composites generate electron-hole pairs under visible light. Then, the photo-generated charges in the CB of CdS are directly transferred to Ni-MOF due to the interface contact and the matched positions of the CB of CdS and the LUMO of Ni-MOF, and the holes are consumed by the sacrificial agent (lactic acid). In this case, electron-hole pairs are effectively separated, Moreover, Ni-MOF containing highly dispersed Ni2+ irons could act as the active site for H 2 generation. Ni-MOF acts as a dual role of electron acceptor and co-catalyst in photocatalytic H 2 production from water. This work could pave the way for further development of semiconductor/MOF composites with enhanced-performance. • The CdS/Ni-MOF composites are successfully synthesized. • The CdS/Ni-MOF composites exhibit high charge separation efficiency. • The CdS/Ni-MOF composites offered enhanced performance in photocatalytic H 2 production. Constructing semiconductor-based photocatalysts with high-performance and excellent stability is a promising approach to achieve optimum photocatalytic H 2 production rate from water splitting. In this study, a novel effective visible-light-driven catalyst, namely, CdS/Ni-MOF, has been successfully synthesized by in-situ growth of CdS nanoparticles on the surface of hollow Ni-based metal-organic framework (Ni-MOF) spheres. The heterogeneous interface contact and matched band position promote charge separation. As a noble-metal-free catalyst, the obtained CdS/Ni-MOF composite having an optimal CdS loading of 40 wt.% exhibits a remarkable H 2 production rate of 2508 μmol/g/h under visible light, which is about eight times higher than that of single CdS. Ni-MOF serves as a station for the rapid transfer of photo-induced electrons, leading to the high photocatalytic performance. Meanwhile, Ni-MOF comprising highly dispersed Ni2+ catalytic sites also acts as co-catalyst, which is beneficial for hydrogen evolution. Therefore, Ni-MOF functions as both an electron acceptor and a co-catalyst in the photocatalytic H 2 production from water. This work highlights the advantages of combining semiconductor and MOF functionalities to fabricate a photocatalyst with enhanced catalytic activity. [ABSTRACT FROM AUTHOR]