Harnessing solar energy to produce usable power is not new, but the technology is constantly evolving and improving. A major development in recent times is the use of perovskite solar cells (PSCs), which are low-weight, highly efficient, flexible solar cells using perovskite (typically a metal-halide material with a specialized structure) crystal structures to absorb light. Though a promising concept, improvements are necessary for PSCs to be able to reach their full potential. Researchers approach these improvements by introducing an additive, 1H-indole-3-carbohydrazide (1H-CBH) to effectively alleviate the main obstacle of PSCs, which are defects leading to loss of energy and efficiency in the cell.

Brain-computer interfaces are moving beyond simple device control toward more dexterous robotic assistance. A new review highlights how noninvasive neural decoding, deep learning, and shared autonomy are helping robotic devices better interpret user intent, reduce control burden, and support future assistive technologies for people with motor impairments and the general population.

Research led by a University of Bristol PhD student has revealed a host of thriving microscopic algae communities in snow and glaciers across one of the most remote locations on Earth.

The behavior of battery electrode slurries under coating-like shear conditions influences the electrical connectivity, resistance, and cycle stability of the final electrode. A new study from Tokyo University of Science uses a method called rheo-impedance spectroscopy to analyze slurry behavior under different shear conditions that simulate real manufacturing. It identifies an intermediate shear rate that disperses particles evenly while preserving conductive networks, leading to lower electrode resistance and better cycle stability.

Researchers have provided the first quantitative characterization of coalescence between a sessile droplet (attached to a fiber) and a pendant droplet (suspended in the continuous phase) – an asymmetric configuration prevalent in industrial fiber coalescers for oily wastewater treatment. Using high‑speed imaging and a Mask R‑CNN deep‑learning model, the study identified three distinct stages. The liquid bridge expansion (Stage I) is governed by capillary pressure difference, insensitive to droplet size ratio. In the oscillation decay stage (Stage II), fiber adhesion rapidly dissipates energy. Crucially, increasing the sessile‑to‑pendant radius ratio to 1.5 significantly reduces the size of secondary droplets generated during neck rupture, offering a direct strategy to improve separation efficiency.

Fiber coalescers are widely used to separate oil from water in petrochemical and other industries. Their performance depends on how dispersed oil droplets merge on fiber surfaces. Most previous studies focused on symmetric coalescence of two sessile droplets sitting on a fiber. In real industrial conditions, however, a more common event is the interaction between a sessile droplet already attached to a fiber and a pendant droplet suspended in the flowing continuous phase. This asymmetric configuration introduces gravity orientation and different kinematic freedom, yet it has remained largely unexplored.

In a study published in ENGINEERING Chemical Engineering, researchers from East China University of Science and Technology used a highspeed camera at 20,000 frames per second and trained a Mask RCNN neural network to automatically segment droplet boundaries and extract morphological parameters with high precision (mean relative error for liquid bridge width only 1.12 %). They systematically investigated coalescence for sessiletopendant radius ratios of 1, 1.25, and 1.5, with water droplets in isooctane under conditions where inertia dominates over viscosity.

The coalescence process comprises three stages. In Stage I (liquid bridge formation), upon contact a liquid bridge expands. The bridge width grows in proportion to the square root of time, confirming the classical capillaryinertial scaling. The driving capillary pressure difference is nearly independent of the droplet size ratio, showing that the initial dynamics are locally controlled by curvature rather than global dimensions.

Stage II (oscillation decay) shows unique behavior. In contrast to symmetric sessilesessile systems where periodic oscillations persist over many cycles, the pendantsessile configuration exhibits rapid energy dissipation because the fiber strongly suppresses oscillations through contact line damping. The amplitude of the capillary wave on the pendant droplet side increases with the size ratio. Neck rupture at the needle tip and fiber junction causes abrupt energy loss, eliminating distinct periodicity and leading to quick equilibrium.

Stage III (stable morphology formation) involves secondary droplet generation from pinchoff of neck filaments. The upper neck (needle side) evolves through hourglass, conical, and dropletformation stages, producing multiple secondary droplets. The lower neck (fiber side) is suppressed by fiber adhesion, generating only a single tiny droplet. Increasing the radius ratio to 1.5 systematically reduces secondary droplet sizes and completely eliminates fiberside breakup.

These findings provide direct guidance for controlling polydisperse droplet emissions in industrial fiber coalescers, enhancing oilwater separation efficiency.

A stretchable, self-healing semiconductor has been developed using hierarchical hydrogen bonds—like mixing Velcro with a zipper. Unlike single-strength bonds, these multi-level bonds work together to balance rigidity and flexibility. It achieves 150% stretchability, 90% electrical healing, and record mobility of 1.01 cm² V⁻¹ s⁻¹ under 150% strain. This solves the trade-off between charge transport, stretchability, and healing ability, paving the way for future stretchable electronics.