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Functional materials revealing mechanochromism behaviors are in high demand for potential applications. Here, we report a 1 : 1 cocrystal of naphtho[2,1-b]benzofuran (BNF) and 1,2,4,5-tetracyanobenzene (TCNB) that displayed a reversible crystal transition (of α- and β-forms) with a resulting change in emission color. The slight differences in cell dimensions, slipping angles between stacking columns, and TCNB orientation enabled this cocrystal to be a sensitive mechanochromic luminescent material. The α-form cocrystal showed significant bathochromic shifts upon being subjected to grinding or isotropic compression, and returned to the original state upon subsequently being subjected to a heating or fuming treatment. Based on detailed spectroscopic and structural analyses, the observed changes in luminescence were mainly attributed to the crystal having undergone a transformation at low pressure and then having formed an amorphous state as a result of damage to its structure. [ABSTRACT FROM AUTHOR]

A practicable strategy to rationally obtain the reversible mechanochromic luminescent (MCL) material with high‐contrast ratio (green versus red) has been established. By introducing a volatile third party (small‐sized solvent molecules) into the lattice of charge transfer (CT) cocrystal of mixed‐stacking 1:1 coronene (Cor.) and napthalenetetracarboxylic diimide (NDI), a noteworthy reconfigurable molecular assembly is ingeniously achieved owing to the loosely packing arrangement as well as weakened intermolecular interactions. Accordingly, the CT excited state, strongly corresponding to the molecular stacking modes, can be intentionally tailored through external stimulus (heating, grinding, or solvent), accompanying distinct changes in photophysical properties. Subsequently, a high‐contrast reversible MCL with highly sensitive and good reproducibility is realized and the underlying mechanism is thoroughly revealed. [ABSTRACT FROM AUTHOR]

Although cocrystallization has provided a promising platform to develop new organic optoelectronic materials, it is still a big challenge to purposely design and achieve specific optoelectronic properties. Herein, a series of mixed‐stacking cocrystals (TMFA, TMCA, and TMTQ) were designed and synthesized, and the regulatory effects of the acceptors on the co‐assembly behavior, charge‐transfer nature, energy‐level structures, and optoelectronic characteristics were systematically investigated. The results demonstrate that it is feasible to achieve effective charge‐transport tuning and photoresponse switching by carefully regulating the intermolecular charge transfer and energy orbitals. The inherent mechanisms underlying the change in these optoelectronic behaviors were analyzed in depth and elucidated to provide clear guidelines for future development of new optoelectronic materials. In addition, due to the excellent photoresponsive characteristics of TMCA, TMCA‐based phototransistors were investigated with varying light wavelength and optical power, and TMCA shows the best performance among all reported cocrystals under UV illumination. [ABSTRACT FROM AUTHOR]

Pi-extended polyaromatics tend to exhibit improved electronic properties with respect to the intrinsic structures. Herein, the rational design of a π-extended diindole-fused diazapentacenone ( IP), with a nine-ring-fused core, obtained by applying an intramolecular Friedel-Crafts diacylation synthetic routine, is reported. The chemical structure, physical properties, and morphology of IP were fully characterized. Serving as an organic cathode material for a lithium-ion battery, the as-prepared nanorods of π-extended IP display higher conductivity and superior electrochemical performance than those of the naked diazapentacenone without diindole fusion. [ABSTRACT FROM AUTHOR]

• ZnIn 2 S 4 /Mn 0.3 Cd 0.7 S 1-x photocatalysts with a Mn-S bond interface were synthesized. • fs-TA probed the kinetics and lifetime of active photogenerated charge carriers. • Various in-situ characteriazations demonstrated a rational Z-Scheme mechanism. • The quantum efficiency for the optimal photocatalyst achieved 32.71 % at 420 nm. Developing a highly effective solar-to-H 2 conversion system is a promising strategy for carbon neutrality. Here, we report a chemically bonded Z-scheme photocatalyst by specifically linking the conduction band site of ZnIn 2 S 4 with the valence band site of Mn 0.3 Cd 0.7 S 1-x. Deviates from the typical van der Waals interactions between two semiconductors, the in-built robust binding force (Mn-S bond) and charge transfer channel facilitates the electron mobility, minimizes detrimental deep charge trapping, and prolongs the active charge lifetime from 983 ps to 4250 ps. The sulfur vacancies in Mn 0.3 Cd 0.7 S 1-x are partially refilled by atoms of the same element in ZnIn 2 S 4 during the in-situ formation of heterojunctions, which promotes and solidates the establishment of interfacial chemical bonds. The optimal photocatalyst achieves a high quantum efficiency of 32.71 % at 420 nm. This study offers a new insight into the development of Z-Scheme heterojunctions via a synergistic approach involving doping, vacancy filling and strong interfacial chemical bonds. [ABSTRACT FROM AUTHOR]