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Understanding the effects of intermolecular interactions on metal‐to‐metal charge transfer (MMCT) is crucial to develop molecular devices by grafting MMCT‐based molecular arrays. Herein, we report a series of solvent‐free {Fe2Co2} compounds sharing the same cationic tetranuclear {[Fe(PzTp)(CN)3]2[Co(dpq)2]2}2+ (PzTp−=tetrakis(pyrazolyl)borate, dpq=dipyrido[3,2‐d:2′,3′‐f]quinoxaline) square units but having anions with different size, including BF4−, PF6−, OTf−, and [Fe(PzTp)(CN)3]−. Intermolecular π⋅⋅⋅π interactions between dpq ligands, which coordinate to cobalt ions in the {[Fe(PzTp)(CN)3]2[Co(dpq)2]2}2+ units, can be modulated by introducing different counterions, regulating the distortion of the CoN6 octahedron and ligand field around the cobalt ions. This change results in different MMCT behavior. Computational analyzes reveal the substantial role of the intermolecular interactions tuned by the presence of different counteranions on the MMCT behavior. [ABSTRACT FROM AUTHOR]

Reported herein are two new polymorphic Co-MOFs (CTGU-5 and -6) that can be selectively crystallized into the pure 2D or 3D net using an anionic or neutral surfactant, respectively. Each polymorph contains a H2O molecule, but differs dramatically in its bonding to the framework, which in turn affects the crystal structure and electrocatalytic performance for hydrogen evolution reaction (HER). Both experimental and computational studies find that 2D CTGU-5 which has coordinates water and more open access to the cobalt site has higher electrocatalytic activity than CTGU-6 with the lattice water. The integration with co-catalysts, such as acetylene black (AB) leads to a composite material, AB&CTGU-5 (1:4) with very efficient HER catalytic properties among reported MOFs. It exhibits superior HER properties including a very positive onset potential of 18 mV, low Tafel slope of 45 mV dec−1, higher exchange current density of 8.6×10−4 A cm−2, and long-term stability. [ABSTRACT FROM AUTHOR]

Cobalt‐MOFs, …… deren Phase durch anionische und neutrale Tenside vorgegeben wird, sind unterschiedlich affin gegenüber eingelagerten Wassermolekülen. Diesen Umstand nutzen D.‐S. Li, C. Sun, X. Bu und Mitarbeiter in ihrer Zuschrift auf S. 13181 für die leistungsstarke elektrokatalytische Wasserstoffentwicklung (HER). Im Bildhintergrund symbolisieren eine Meereswelle und der Drei‐Schluchten‐Damm das Potenzial von Wasser als “grüne” Energiequelle. Fortschritte bei der Wasserspaltung ergänzen die Nutzung dieser Energieformen. [ABSTRACT FROM AUTHOR]