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In pursuit of universal access to clean water, photocatalytic water remediation using metal–organic frameworks (MOFs) emerges as a strong alternative to the current wastewater treatment methods. In this study, we explore a unique Ti-based MOF comprised of 2D secondary-building units (SBUs) connected via biphenyl dicarboxylic acid (H2bpdc) ligands – denoted as COK-47 – as a visible-light-driven photocatalyst for organic dye degradation. Synthesized via a recently developed microwave-assisted method, COK-47 exhibits high hydrolytic stability, demonstrates a strong dye uptake, and shows noteworthy dye-degradation performance under UV, visible, and solar light, outperforming benchmark TiO2 and MIL-125-Ti photocatalysts. Due to its nanocrystalline structure and surface termination with organic linkers, COK-47 exhibits selective degradation of cationic pollutants while remaining inert towards anionic dyes, thus highlighting its potential for selective oxidation reactions. Mechanistic studies reveal the involvement of superoxide radicals in the degradation process and emphasize the need to minimize the recombination of photogenerated electron–hole pairs to achieve optimal performance. Post-catalytic studies further confirm the high stability and reusability of COK-47, making it a promising photocatalyst for water purification, organic transformation, and water splitting reactions under visible light. [ABSTRACT FROM AUTHOR]

This study utilizes Social Information Processing (SIP) theory to investigate the relationship between organizational preventive actions (substantive vs. symbolic), employee preventive behavior, the mediating role of conspiracy beliefs, and moderating role of leadership integrity in the context of Covid‐19. The study explains leadership integrity as a boundary condition to facilitate or hinder the mediated relationship between organizational actions and employee preventive behavior (EPB). The hypothesized model was tested using partial least square structural equation modeling (PLS‐SEM) on two‐wave data collected from 281 respondents. The results revealed that substantive actions do not predict EPB directly but through conspiracy beliefs. Contrary to these, symbolic actions negatively predict EPB directly. Leadership integrity moderates the relationship between substantive actions and conspiracy beliefs, while the interaction effect with symbolic actions is not supported. The findings of this study caution managers to walk their talk because employees critically observe the most apparent actions, especially when management fails to practice them. The study contributes to social information processing theory by pointing to leadership integrity as a source of authenticity to curb the negative impact of symbolic actions and catalyst the effect of substantive actions on employee preventive behavior. [ABSTRACT FROM AUTHOR]

We report two Ni12 multicubane topologies enclosed in the polyanions [Ni12(OH)9(WO4)3(PO4)(B-α-PW9O34)3]21−{Ni12W30} and [Ni12(OH)9(HPO4)3(PO4)(B-α-PW9O34)(A-α-PW9O34)2]21−{Ni12W27} that magnetically behave as Ni12 units clearly distinguishing them from typical Ni4 cubanes as shown by magnetic studies together with high field and frequency electron paramagnetic resonance (HFEPR). Beyond the unprecedented static properties, {Ni12W30} shows the unusual coexistence of slow relaxation of the magnetization and a diamagnetic ground state (S = 0), providing the unique opportunity of studying the essentially elusive magnetic relaxation behavior in excited states. The cubane-topology dependent activity of {Ni12W30} and {Ni12W27} as homogeneous HER photocatalysts unveils the structural key features significant for the design of photocatalysts with efficient charge utilization exemplified by high quantum yields (QY) of 10.42% and 8.36% for {Ni12W30} and {Ni12W27}, respectively. [ABSTRACT FROM AUTHOR]

Production of green hydrogen (H 2 ) is a sustainable process able to address the current energy crisis without contributing to long-term greenhouse gas emissions. Many Ag-based catalysts have shown promise for light-driven H 2 generation, however, pure Ag-in its bulk or nanostructured forms-suffers from slow electron transfer kinetics and unfavorable Ag─H bond strength. It is demonstrated that the complexation of Ag with various chalcogenides can be used as a tool to optimize these parameters and reach improved photocatalytic performance. In this work, metal-organic-chalcogenolate assemblies (MOCHAs) are introduced as effective catalysts for light-driven hydrogen evolution reaction (HER) and investigate their performance and structural stability by examining a series of AgXPh (X = S, Se, and Te) compounds. Two catalyst-support sensitization strategies are explored: by designing MOCHA/TiO 2 composites and by employing a common Ru-based photosensitizer. It is demonstrated that the heterogeneous approach yields stable HER performance but involves a catalyst transformation at the initial stage of the photocatalytic process. In contrast to this, the visible-light-driven MOCHA-dye dyad shows similar HER activity while also ensuring the structural integrity of the MOCHAs. The work shows the potential of MOCHAs in constructing photosystems for catalytic H 2 production and provides a direct comparison between known AgXPh compounds., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

We report two Ni 12 multicubane topologies enclosed in the polyanions [Ni 12 (OH) 9 (WO 4 ) 3 (PO 4 )(B-α-PW 9 O 34 ) 3 ] 21- {Ni 12 W 30 } and [Ni 12 (OH) 9 (HPO 4 ) 3 (PO 4 )(B-α-PW 9 O 34 )(A-α-PW 9 O 34 ) 2 ] 21- {Ni 12 W 27 } that magnetically behave as Ni 12 units clearly distinguishing them from typical Ni 4 cubanes as shown by magnetic studies together with high field and frequency electron paramagnetic resonance (HFEPR). Beyond the unprecedented static properties, {Ni 12 W 30 } shows the unusual coexistence of slow relaxation of the magnetization and a diamagnetic ground state ( S = 0), providing the unique opportunity of studying the essentially elusive magnetic relaxation behavior in excited states. The cubane-topology dependent activity of {Ni 12 W 30 } and {Ni 12 W 27 } as homogeneous HER photocatalysts unveils the structural key features significant for the design of photocatalysts with efficient charge utilization exemplified by high quantum yields (QY) of 10.42% and 8.36% for {Ni 12 W 30 } and {Ni 12 W 27 }, respectively., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Achieving light-driven splitting of water with high efficiency remains a challenging task on the way to solar fuel exploration. In this work, to combine the advantages of heterogeneous and homogeneous photosystems, we covalently anchor noble-metal- and carbon-free thiomolybdate [Mo 3 S 13 ] 2- clusters onto photoactive metal oxide supports to act as molecular co-catalysts for photocatalytic water splitting. We demonstrate that strong and surface-limited binding of the [Mo 3 S 13 ] 2- to the oxide surfaces takes place. The attachment involves the loss of the majority of the terminal S 2 2- groups, upon which Mo-O-Ti bonds with the hydroxylated TiO 2 surface are established. The heterogenized [Mo 3 S 13 ] 2- clusters are active and stable co-catalysts for the light-driven hydrogen evolution reaction (HER) with performance close to the level of the benchmark Pt. Optimal HER rates are achieved for 2 wt % cluster loadings, which we relate to the accessibility of the TiO 2 surface required for efficient hole scavenging. We further elucidate the active HER sites by applying thermal post-treatments in air and N 2 . Our data demonstrate the importance of the trinuclear core of the [Mo 3 S 13 ] 2- cluster and suggest bridging S 2 2- and vacant coordination sites at the Mo centers as likely HER active sites. This work provides a prime example for the successful heterogenization of an inorganic molecular cluster as a co-catalyst for light-driven HER and gives the incentive to explore other thio(oxo)metalates., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)