Side-chain engineering has been shown to be an important strategy to optimize Y-series nonfullerene acceptors (NFAs). Most previous reports were focusing on changing the branching positions and size of the alkyl side chains on Y6. In this paper, we investigate the influence of the orientation of side chains on the properties of NFAs and the performance of the organic solar cells (OSCs). Three isomeric NFAs named o-BTP-PhC6, m-BTP-PhC6, and p-BTP-PhC6 are designed by changing the substitution positions and thus orientations of the side chains attached to the central core. Our studies show that the optimal side-chain orientation can be achieved by the meta-positioned hexylphenyl group (of the m-BTP-PhC6 molecule), which introduces significant beneficial effects on optical absorption, intermolecular packing and phase separation of the NFAs. By pairing a donor polymer PTQ10 with m-BTP-PhC6, device efficiencies of 17.7% can be achieved, which is among the best values for PTQ10-based nonfullerene OSC devices so far. These results reveal that regulating side-chain orientations of Y-series NFAs is a promising strategy to achieve favorable morphology, and high charge mobility and solar cell performances.

We proposed a new full-color display framework QD-OLEDs, where blue OLEDs are used as pump light, and red and green QDs are printed on color filters as color conversion layers.

Colloidal quantum dot (QD) emitters show great promise in the development of next-generation displays. Although various solution-processed techniques have been developed for nanomaterials, high-resolution and uniform patterning technology amicable to manufacturing is still missing. Here, we present large-area, high-resolution, full-color QD patterning utilizing a selective electrophoretic deposition (SEPD) technique. This technique utilizes photolithography combined with SEPD to achieve uniform and fast fabrication, low-cost QD patterning in large-area beyond 1,000 pixels-per-inch. The QD patterns only deposited on selective electrodes with precisely controlled thickness in a large range, which could cater for various optoelectronic devices. The adjustable surface morphology, packing density and refractive index of QD films enable higher efficiency compared to conventional solution-processed methods. We further demonstrate the versatility of our approach to integrate various QDs into large-area arrays of full-color emitting pixels and QLEDs with good performance. The results suggest a manufacture-viable technology for commercialization of QD-based displays.

Flexible Zn–MnO₂ batteries as wearable electronic power source have attracted much attention in recent years due to their low cost and high safety. To promote the practical application of flexible Zn–MnO₂ batteries, it is imperative to develop flexible, mechanically robust and high performance solid state electrolyte. Herein, we construct a rechargeable quasi-solid-state zinc ion battery using kappa-carrageenan bio-polymer electrolyte. The kappa-carrageenan electrolyte is eco-friendly, low cost, and highly conductive (3.32 × 10⁻² S cm⁻¹ at room temperature). The mechanical robustness of kappa-carrageenan electrolyte is further reinforced by using a rice paper as scaffold. Benefiting from high ionic conductivity of the bio-polymer electrolyte, our zinc ion battery delivers a significant high energy density and power density (400 W h kg⁻¹ and 7.9 kW kg⁻¹, respectively), high specific capacity (291.5 mA h g⁻¹ at 0.15 A g⁻¹), fast charging and discharging capability (120.0 mA h g⁻¹ at 6.0 A g⁻¹). The zinc ion battery with bio-polymer electrolyte also shows excellent cycling stability and high bending durability. This work brings new research opportunities in developing low-cost flexible solid-state zinc ion batteries using green natural polymer.

Rechargeable aqueous zinc‐ion batteries (ZIBs) have been considered as a promising candidate for the large‐scale energy storage device owing to their low cost and high safety. However, the practical application of aqueous ZIBs at low temperature environment is hindered by the freezing aqueous electrolytes, which leads to a sharp drop in ionic conductivity, and thereby a rapid deterioration of battery performance. Herein, a chaotropic salt electrolyte based on low concentration aqueous Zn(ClO₄)₂ with superior ionic conductivity under low temperature (4.23 mS/cm at −50°C) is reported. The anti‐freezing methodology introduced here is completely different from conventional freeze‐resistant design of using “water‐in‐salt” electrolyte, cosolvents, or anti‐freezing agent additives strategy. Experimental analysis and molecular dynamics simulations reveal that the as‐prepared Zn(ClO₄)₂ electrolyte possesses faster ionic migration compared with other commonly used Zn‐based salts (i.e., Zn(CF₃SO₃)₂ and ZnSO₄) electrolyte. It is found that Zn(ClO₄)₂ electrolyte can suppress the ice crystal construction by forming more hydrogen bonds between solute ClO₄⁻ and solvent H₂O molecules, thus leading to a superior anti‐freezing property. The fabricated ZIBs using this aqueous electrolyte exhibits a dramatically enhanced specific capacity, remarkable rate capability, and great cycling stability over a wide temperature range, from −50 to 25°C. The aqueous ZIBs also exhibit an outstanding energy density of 238.4 Wh/kg without compromising the power density (7.9 kW/kg) under −20°C. Moreover, the assembled aqueous ZIBs can also cycle stably over 1000 cycles at an ultra‐low −50°C. The high‐safety and cost‐effective chaotropic salt electrolyte presented here is a promising strategy for low temperature energy storage application. image