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Semiconductor nanocrystals are at the frontier of energy conversion research owing to their tunable optoelectronic attributes and versatile surface activities. Here high‐surface‐area mesoporous frameworks comprising linked CdIn2S4 nanocrystals as efficient catalysts are presented for visible‐light‐driven hydrogen production. X‐ray total scattering analysis discloses hexagonally‐structured CdIn2S4 thiospinel nanoparticles forming the porous structure. Further analytic results indicate that these newly‐made ensembles possess an open‐up architecture that is highly conductive and susceptible to modification. Through appropriate selection of the synthesis conditions, it is demonstrated that the present synthetic protocol is general, allowing the preparation of porous materials from thiospinel nanoparticles with various sizes and compositions. This study shows that coupling of CdIn2S4 mesostructures and Ni2P nanosheets substantially expedites the kinetics of water photo‐splitting by effectively reinforcing the separation of photogenerated carriers at the interfaces. Thus, mesoporous Ni2P/CdIn2S4 heterojunctions instigate a remarkable improvement in the hydrogen generation rate (≈29.3 mmol h−1 gcat−1), presenting an apparent quantum yield of 61.7% at 420 nm monochromatic light. A combination of electrochemical and spectroscopic studies unveils a pertinent mechanistic link between the charge‐transfer dynamics and intrinsic photochemical activity in these nanostructures. [ABSTRACT FROM AUTHOR]

Reaction between Mn(NO3)2 ⋅ 6H2O, Zn(NO3)2 ⋅ 6H2O, 1,3,5‐tri(2‐hydroxyethyl)‐1,3,5‐triazacyclohexane (H3L) and pyrazole in MeOH under basic conditions leads to the formation of the decanuclear complex [MnIII6MnII2ZnII2(L)2(pyr)4O4(OH)4(NO3)2 (MeOH)2(H2O)4](NO3)2 ⋅ Η2Ο (1 ⋅ Η2Ο). The metallic core of the cationic cluster consists of a central hexagonal‐bipyramidal {MnIII4MnII2ZnII2} unit connected to two peripheral trivalent Mn centers arranged in a "trans" fashion, with one MnIII center lying above and one MnIII center below the hexagonal plane. Replacing Mn(NO3)2 ⋅ 6H2O with MnBr2 ⋅ 4H2O and repeating the same reaction leads to the formation of the related, neutral decanuclear complex [MnIII6MnII2ZnII2(L)2(pyr)4O4(OH)4Br4(H2O)2] (2), displaying the same metallic core as 1. Addition of THF to the reaction mixture that produces (2) affords the neutral dodecanuclear complex [MnIII6MnII2ZnII4(L)2(pyr)6O4(OH)4Br6(H2O)4] ⋅ 8THF (3 ⋅ 8THF), whose metallic skeleton retains the central hexagonal‐bipyramidal {MnIII4MnII2ZnII2} unit found in 1 and 2 but is now connected to two peripheral {MnIIIZnII} units. Magnetic susceptibility and magnetization measurements carried out in the T=2–300 K temperature range and in fields up to B=7.0 T for all three complexes reveal dominant antiferromagnetic exchange interactions. [ABSTRACT FROM AUTHOR]