A highly stable pillared and double-walled zinc(II) metal-organic framework with regular nanochannels displays single-crystal to single-crystal transformation upon desolvation and a large quantity of iodine uptake, controlled release, and electrical conductivity elevation due to synergy between the iodine guests and the host framework.

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Driven by the rapidly increasing demand for technological applications, multifunctional materials have been one important research area, which are expected to enhance the capacity and versatility of materials in various applications. Nevertheless, combining more than three functions in one molecular compound is still a challenge. Molecular solid–solid phase transition materials could exhibit switchable properties, which could have potential applications such as switches, sensors, and memory devices. However, these switchable molecular materials are rarely researched as thermal energy storage materials. In this work, we report the coexistence of thermal energy storage and magnetic-optic-electric triple switching in a plastic crystal, trimethyl­chloro­methyl ammonium tetrachloro­ferrate­(III), ([(CH3)3­NCH2Cl]­[FeCl4], referred to as 1). 1 undergoes plastic phase transition at near room temperature (326 K) induced by the order–disorder of the ions. The magnetic-optic-electric triple switching in 1 could be triggered by temperature stimuli near room temperature. Meanwhile, with utilization of large latent heat during the phase transition process and sensible heat, the energy storage in 1 is up to 107 J g–1 from 293 to 343 K, demonstrating its thermal energy storage application in solar energy systems and industrial sectors. This work particularly exhibits the advantages of plastic molecular materials as thermal energy storage materials and introduces the thermal energy storage into the multi-switchable plastic phase transition molecular materials, which will give extra flexibility for the design of new types of multifunctional materials.

Inorganic-organic hybrid molecular multiferroic and magnetoelectric materials, similar to multiferroic oxide compounds, have recently attracted increasing attention because they exhibit diverse architectures, a flexible framework, fascinating physics, and potential magnetoelectric functionalities in novel multifunctional devices such as energy transformation devices, sensors, and information storage systems. Herein, the classification of multiferroicity and magnetoelectricity is briefly outlined and then the recent advances in the multiferroicity and magnetoelectricity of inorganic-organic hybrid molecular materials, particularly magnetoelectricity and the relevant magnetoelectric mechanisms and their categories are summarized. In addition, a personal perspective and an outlook are provided.

In recent years, molecular ferroelectrics have received more and more attention. Nevertheless, the study of multiaxial molecular ferroelectrics is relatively rare, which significantly restricts the development of their applications in thin films and other potential fields. Here we demonstrate the characteristics of a room-temperature lead-free multiaxial inorganic–organic hybrid ferroelectric material [(CH3)2NH2] [C6H5CH2NH3]2BiBr6 (1), which goes through a distinctly reversible phase transition around 386 K and possesses six equivalent ferroelectric directions. At 330 K, the remnant polarization (P r) of 1 is ∼1.0 μC·cm–2, and the coercive field (E c) of 1 is 20 kV·cm–1. The multiaxial and switching polarization behaviors of 1 were declared with piezoresponse force microscopy (PFM). Notably, the emergence of six equivalent ferroelectric directions is induced by the easily disordered cations and highly geometrically symmetrical anions, because they usually lead to a large symmetry change in the order–disorder types of ferroelectrics. This work provides an effective approach to construct molecular multiaxial ferroelectrics.

The GaAsSb-based quantum well plays a very important role in optoelectronic devices due to its excellent wavelength tunability. When the dimension reduces, the quantum confinement effect will take place and the quantum well in nanowires will show many interesting characteristics. GaAsSbbased quantum-well nanowires are of contemporary interest. However, the properties of the quasitype-II structure in a single quantum well nanowire have been rarely investigated. Here, we grow GaAs/GaAs 0.92 Sb 0.08 /GaAs coaxial single quantum-well nanowires and discussed their powerdependent and temperature-dependent photoluminescence. We find that due to the small band offset of conduction bands, both type-I like and type-II like emission exist in our nanowires. When electrons obtain enough thermal energy through collisions or surrounding environment, they will overcome the barrier and diffuse to the GaAs conduction band, which contributes to the type-II like recombination. These results show the optical property of the quasi-type-II quantum well in nanowires, which can pave the way toward future nanoscale quantum well devices. Published by AIP Publishing.

Magnetoelectric materials with a large magnetoelectric response, a low operating magnetic (or electric) field, and a room‐temperature (or higher) operating temperature are of key importance for practical applications. However, such materials are extremely rare because a large magnetoelectric response often requires strong coupling between spins and electric dipoles. Herein, an example of a magnetoelectric composite is prepared by using a room‐temperature multiaxial molecular–ionic ferroelectric, tetramethylammonium tetrachlorogallate(III) (1). Investigation of the magnetoelectric effect of the magnetoelectric laminate composite indicates that its room‐temperature magnetoelectric voltage coefficient (αME) is as high as 186 mV cm−1 Oe−1 at HDC = 275 Oe and at the HAC frequency of ≈39 kHz, providing a valid approach for the preparation of magnetoelectric materials and adding a new member to the magnetoelectric material family.