We synthesized luminescent CsPbBr3 nanocrystals with a high quantum yield and realized patterning and color-purity light-emitting diode applications.

Fiber‐shaped micro‐supercapacitors (micro‐SCs) have attracted enormous interest in wearable electronics due to high flexibility and weavability. However, they usually present a low energy density because of inhomogeneity and less pores. Here, we demonstrate a microfluidic‐directed strategy to synthesize homogeneous nitrogen‐doped porous graphene fibers. The porous fibers‐based micro‐SCs utilize solid‐state phosphoric acid/polyvinyl alcohol (H3PO4/PVA) and 1‐ethyl‐3‐methylimidazolium tetrafluoroborate/poly(vinylidenefluoride‐co‐hexafluoropropylene) (EMIBF4/PVDF‐HFP) electrolytes, which show significant improvements in electrochemical performances. Ultralarge capacitance (1132 mF cm−2), high cycling‐stability, and long‐term bending‐durability are achieved based on H3PO4/PVA. Additionally, high energy densities of 95.7–46.9 µWh cm−2 at power densities of 1.5–15 W cm−2 are obtained in EMIBF4/PVDF‐HFP. The key to higher performances stems from microfluidic‐controlled fibers with a uniformly porous network, large specific surface area (388.6 m2 g−1), optimal pyridinic nitrogen (2.44%), and high electric conductivity (30785 S m−1) for faster ion diffusion and flooding accommodation. By taking advantage of these remarkable merits, this study integrates micro‐SCs into flexible and fabric substrates to power audio–visual electronics. The main aim is to clarify the important role of microfluidic techniques toward the architecture of electrodes and promote development of wearable electronics.

We demonstrated a new strategy to construct high-performance micro-SCs based on microfluidic-oriented core–sheath structured polyaniline nanorod arrays/graphene fibers.

Supercapacitors, which store electrical energy through reversible ion on the surface of conductive electrodes have gained enormous attention for variously portable energy storage devices. Since the capacitive performance is mainly determined by the structural and electrochemical properties of electrodes, the electrodes become more crucial to higher performance. However, due to the disordered microstructure and low electrochemical activity of electrode for ion tortuous migration and accumulation, the supercapacitors present relatively low capacitance and energy density. Here we report a high-performance supercapacitor based on polyaniline/vertical-aligned carbon nanotubes (PANI/VA-CNTs) nanocomposite electrodes where the vertical-aligned-structure is formed by the electrochemical-induction (0.75 V). The supercapacitor displays large specific capacitance of 403.3 F g−1, which is 6 times higher than disordered CNTs in HClO4 electrolyte. Additionally, the supercapacitor can also present high specific capacitance (314.6 F g−1), excellent cycling stability (90.2% retention after 3000 cycles at 4 A g−1) and high energy density (98.1 Wh kg−1) in EMIBF4 organic electrolyte. The key to high-performance lies in the vertical-aligned-structure providing direct path channel for ion faster diffusion and high electrochemical capacitance of polyaniline for ion more accommodation.

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