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Herein, we report extended π‐conjugated arylazopyrazole and arylazoisoxazole photoswitches towards tuning and modulation of their intrinsic properties. In this regard, we systematically introduced phenyl, styryl, (triphenylvinyl)styryl, phenylethynyl groups at ortho, meta, and para positions relative to the azo unit to extend the π‐conjugation and vary the electronic coupling. In addition, the heterocyclic substituents were also modified. Overall, 20 photoswitches with modular substituents have been synthesized and studied for the photoswitching ability and thermal relaxations of Z isomers in the solution phase and solid state. Besides deciphering the importance of extending conjugation in photoswitching characteristics, intriguing properties such as mechanochromism and reversible bidirectional photochromism in the solid state were also unravelled. Through extensive spectroscopic studies, we envisage the effect of electronic coupling due to π‐conjugation and its impact on longer wavelength light‐induced photoswitching that holds several application potentials. [ABSTRACT FROM AUTHOR]

Ag3BiI6 (ABI) is one of the most widely explored lead‐free perovskite‐inspired materials for eco‐friendly solar cell applications. However, despite the intense research efforts, the photovoltaic performance of ABI‐based devices remains very modest, primarily due to poor film morphology and ineffective charge extraction. This work aims at investigating the potential benefits of a thermally evaporated cesium iodide (CsI) interlayer on the performance of ABI‐based solar cells. Upon the addition of CsI atop the ABI layer in the device stack, the solar cells deliver a power conversion efficiency (PCE) of 2.27%. This is the highest efficiency reported for ABI solar cells employing a similar device architecture. It is found that the enhancement in PCE is largely due to improvement in the ABI|hole transport layer interface upon the introduction of CsI interlayer. The improvement is largely ascribed to enhanced surface coverage upon introduction of CsI interlayer, as evidenced by our comprehensive microscopy studies. Furthermore, impedance spectroscopy analysis is employed to provide further insights into the changes in charge transfer dynamics interlayer that dictate the enhancement of fill factor and short‐circuit current density in the devices. The findings indicate that the addition of CsI promotes charge transfer and minimizes recombination losses. [ABSTRACT FROM AUTHOR]

As biomimicry advances, liquid crystal elastomers (LCEs) are gaining attention for their (multi-)stimuli-responsiveness and reversible shape morphing. Introduction of dynamic bonds into the LCEs provides versatile means towards programmable shape morphing and adaptation to environmental cues, and new designs for dynamic LCEs are actively sought for. Here, we present a supramolecular LCE that integrates shape memory programming, humidity sensitivity, and photochemical actuation. By utilizing hydrogen bonding crosslinks, the LCE gains shape memory functionality, enabling arbitrary shape programming and photochemical actuation. By breaking the supramolecular crosslinks via base treatment, the LCE becomes hygroscopic and humidity sensitive, yet maintains photochemical deformability. These two states enable different types of soft actuator demonstrations both in air and under water, adding to the versatility and programmability of light-driven shape-changing LCEs.