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Abstract Layered hybrid organic–inorganic perovskites offer a unique platform to engineer thermal, mechanical, and spintronic properties through molecular design. This perspective highlights recent advances in characterizing and tuning thermal conductivity and elastic modulus in layered hybrid metal halide perovskites with emphasis on measurement methodologies and the interplay among molecular structure, dynamics, and materials properties. We discuss how organic cations in the perovskites modulate their thermal transport and mechanical behavior, and introduce the emergence of chiral phonons and the recently discovered chiral-phonon-activated spin Seebeck effect in them. These insights reveal pathways to decouple thermal and mechanical properties and enable spin functionality. We conclude by outlining future directions for advancing fundamental understandings and unlocking new functionalities in layered hybrid perovskitesviamolecular engineering. Graphic abstract 

Direct Contact Membrane Distillation (DCMD) is a promising desalination technique that can utilize low-grade energy to desalinate water. This study presents a microscale approach to simulate evaporation and condensation inside hydrophobic fibrous membranes. The novelty of the proposed method is that it incorporates the microstructure of the membranes in the calculations and can potentially be used for optimizing membrane’s microstructure. In particular, the model predicts how feed or permeate pressures and temperatures impact the rate of freshwater production. The simulations were conducted in computational domains that mimic the internal geometry of fibrous DCMD membranes in 2-D. The air–water interfaces (AWIs) over the feed and permeate sides of the membrane were simulated using an in-house Pore Morphology Method (PMM) MATLAB code. The resulting wetting and non-wetting phases were then exported to ANSYS using a cell-marking method. The Schrage phase change model was coupled with the ANSYS’s volume of fluid (VOF) solver to simulate water evaporation at the feed AWI and condensation at the permeate AWI. The simulations revealed that increasing the feed or permeate pressure can, to some extent, improve the rate of freshwater production by bringing the feed and permeate AWIs closer to one another and by increasing their surface areas. It was also observed that increasing the feed and permeate temperatures, while keeping their temperature difference constant, can enhance the freshwater production rate significantly. 

Recognizing the coupling between ferroelectricity and chirality in optically active ferroelectrics opens a route for manipulating chirality via ferroelectricity under an external electric field, enabling control over chirality-dependent quantum states. Here, we report the experimental demonstration of the coupling between ferroelectricity and phonon chirality in the molecular ferroelectric triglycine sulfate. By electrically switching the crystal chirality, we achieve reversible and device-compatible control of phonon chirality, as revealed by in situ time-resolved magneto-optical Kerr effect measurements. The Kerr rotation reverses with electric-field switching, while phonon chirality vanishes in the paraelectric phase and is tunable in the racemic ferroelectric state. Furthermore, density functional theory calculations and circularly polarized Raman spectroscopy further corroborate the opposite circular phonon motions. These results establish an electrically addressable coupling pathway linking ferroelectricity, structural chirality, chiral phonons, and spin, opening a route toward chiral-phonon-enabled spin and phonon control technologies based on ferroelectric materials. 

Chirality-induced spin selectivity (CISS) is a striking quantum phenomenon in which electron transport through chiral molecules leads to spin polarization—even in the absence of external magnetic fields or magnetic components. Although observed in systems such as DNA, helicenes, proteins, and polymers, the fundamental physical origin of CISS remains unresolved. Here, we introduce a time-dependent relativistic four-current framework, in which charge and current densities evolve according to the time-dependent variational principle. Real-time relativistic four-current simulations enable direct analysis of helical currents and induced magnetization dynamics. Applied to helicenes—axially chiral molecules lacking stereocenters—our simulations reveal curvature-induced helical electron currents that generate spontaneous magnetic fields aligned along the molecular axis. These fields are handedness-dependent and reach magnitudes of 10−1 T per single helicene strand. Our results suggest that CISS may arise from intrinsic, relativistic, curvature-induced helical currents and the associated magnetic fields within chiral molecules. This four-current mechanism offers a self-contained explanation for the driving force underlying spin selectivity, independent of interfacial effects or unphysically enhanced spin–orbit coupling. Furthermore, our results provide a new perspective that offers a unifying framework with the potential to reconcile many existing hypotheses and theoretical models, while also suggesting several testable predictions that can be examined experimentally. 

As electric-vehicle (EV) sales keep rising, EV-related incidents are becoming more frequent, yet many first responders still rely on traditional training and feel unprepared for the new challenges. To help address this gap, we created a virtual reality (VR) training system that offers an interactive and immersive learning environment without real-world risks. We compared the VR system with two other learning formats—text-based and video-based—in a controlled study that enrolled university students and firefighters. Participants were randomly assigned to one format, completed a self-evaluation before and after training, then took a multiple-choice test immediately afterward. The identical test was sent to them again two weeks later to measure long-term retention. Usability, perceived usefulness, and workload were also recorded. All three methods improved participants’ knowledge. VR and text showed better results than video in immediate learning. However, VR stood out for long-term retention, showing the smallest drop in scores after 2 weeks. Participants also found VR experience more engaging and realistic. These findings suggest that VR can be a powerful tool to better prepare first responders for EV emergencies.