For organic solar cells to be competitive, the light-absorbing molecules should simultaneously satisfy multiple key requirements, including weak-absorption charge transfer state, high dielectric constant, suitable surface energy, proper crystallinity, etc. However, the systematic design rule in molecules to achieve the abovementioned goals is rarely studied. In this work, guided by theoretical calculation, we present a rational design of non-fullerene acceptor o-BTP-eC9, with distinct photoelectric properties compared to benchmark BTP-eC9. o-BTP-eC9 based device has uplifted charge transfer state, therefore significantly reducing the energy loss by 41 meV and showing excellent power conversion efficiency of 18.7%. Moreover, the new guest acceptor o-BTP-eC9 has excellent miscibility, crystallinity, and energy level compatibility with BTP-eC9, which enables an efficiency of 19.9% (19.5% certified) in PM6:BTP-C9:o-BTP-eC9 based ternary system with enhanced operational stability.

Supramolecular assemblies hold great promise for advanced chiral materials because of their structural diversity and dynamic features, but their low chiroptical activity limits practical applications. We report hierarchical supramolecular assemblies with giant chiroptical activity and mechanical attributes achieved through coassembly of achiral amphiphilic unimolecular micelles and chiral additives. Chiral fibrillar assemblies emerge from the nanostructured environment imposed by the micelles, driven by progressive chirality transfer through multiple hydrogen bonds between components. Integrating multifarious achiral luminescent molecules and nanocrystals into these assemblies leads to full-color circularly polarized luminescence–active materials with dissymmetry factors of ~10 ⁻¹ . A concentration-dependent chirality inversion is accessed through tailoring the coassembly kinetics. This strategy enables efficient red CPL, crucial for quantum and optical technologies.

Polymorphism of nonfullerene acceptors enhances electron transport properties and potentially impacts the performance of organic electronic devices.

Human perception systems are highly refined, relying on an adaptive, plastic, and event-driven network of sensory neurons. Drawing inspiration from Nature, neuromorphic perception systems hold tremendous potential for efficient multisensory signal processing in the physical world; however, the development of an efficient artificial neuron with a widely calibratable spiking range and reduced footprint remains challenging. Here, we report an efficient organic electrochemical neuron (OECN) with reduced footprint (<37 mm ² ) based on high-performance vertical OECT (vOECT) complementary circuitry enabled by an advanced n-type polymer for balanced p-/n-type vOECT performance. The OECN exhibits outstanding neuronal characteristics, capable of producing spikes with a widely calibratable state-of-the art firing frequency range of 0.130 to 147.1 Hz. Leveraging this capability, we develop a neuromorphic perception system that integrates mechanical sensors with the OECN and integrates them with an artificial synapse for tactile perception. The system successfully encodes tactile stimulations into frequency-dependent spikes, which are further converted into postsynaptic responses. This bioinspired design demonstrates significant potential to advance cyborg and neuromorphic systems, providing them with perceptual capabilities.

The order of molecular aggregation at the donor–acceptor interface strongly affects the charge generation and extraction properties, determining the performance of organic electronic devices. Herein, we focused on bilayer organic solar cells and selected a combination of solid- and solvent-additives, namely 1-chloronaphthalene (CN) and trans-bis(dimesitylboron)stilbene (BBS), to tune the acceptor's molecular arrangement in the bilayer active layer structure. When CN alone was added, the molecular orientation in the acceptor film changed from face-on to edge-on, and the crystallinity of the thin film significantly increased owing to the J-aggregation of the acceptor. While dual additives were used, a flocculent morphology was attained, leading to further increased crystallinity and an improved order of molecular aggregation, thus reducing the trap states in the acceptor layer. As a result, using dual additives resulted in decreased trap-assisted charge recombination and enhanced charge extraction, hence an excellent fill factor and optimum efficiency of 19.32%. The findings elucidate that morphology optimization using dual additives can strengthen the molecular arrangement order, which is a practical approach for high-performing bilayer organic solar cells.

The rapid development of non-fullerene acceptors (NFAs) has placed increasing demands on polymer donors and there is still room for optimization of the currently available top-performing polymer donors to work perfectly with the state-of-the-art NFAs. To further develop and fine-tune the best-performing polymer donors, random ternary copolymerization is a simple and powerful strategy, in which the search for a suitable and easily accessible third component is the challenge. Herein, a series of terpolymer donors OPz11, OPz12, OPz13 and OPz14 are synthesized by incorporating varying fractions of the ester-substituted thiazole (E-Tz) unit into the D18 polymer. Notably, the subtle E-Tz content brings optimization in the energy levels, electrostatic potentials (ESPs), molecular aggregation, miscibility and morphology, as revealed by the open circuit voltage (V_OC) improvement from 856.1 to 865.3 mV, and fill-factor (FF) enhancement from 74.34% to 78.71%. Finally, an exciting power conversion efficiency (PCE) of 18.42% is obtained from OPz11:Y6 devices, and is among the highest values reported for PSCs. This work illustrates that the accessible E-Tz unit is a promising building block to construct terpolymer donors for high-performance organic photovoltaic cells, and random ternary copolymerization is a flexible and promising strategy for photovoltaic materials development.