Uniform Luminous Perovskite Nanofibers with Color‐Tunability and Improved Stability Prepared by One‐Step Core/Shell Electrospinning

Abstract

A one-step core/shell electrospinning technique is exploited to fabricate uniform luminous perovskite-based nanofibers, wherein the perovskite and the polymer are respectively employed in the core and the outer shell. Such a coaxial electrospinning technique enables the in situ formation of perovskite nanocrystals, exempting the needs of presynthesis of perovskite quantum dots or post-treatments. It is demonstrated that not only the luminous electrospun nanofibers can possess color-tunability by simply tuning the perovskite composition, but also the grain size of the formed perovskite nanocrystals is largely affected by the perovskite precursor stoichiometry and the polymer solution concentration. Consequently, the optimized perovskite electrospun nanofiber yields a high photoluminescence quantum yield of 30.9%, significantly surpassing the value of its thin-film counterpart. Moreover, owing to the hydrophobic characteristic of shell polymer, the prepared perovskite nanofiber is endowed with a high resistance to air and water. Its photoluminescence intensity remains constant while stored under ambient environment with a relative humidity of 85% over a month and retains intensity higher than 50% of its initial intensity while immersed in water for 48 h. More intriguingly, a white light-emitting perovskite-based nanofiber is successfully fabricated by pairing the orange light-emitting compositional perovskite with a blue light-emitting conjugated polymer.

Flexible Solar Yarns with 15.7% Power Conversion Efficiency, Based on Electrospun Perovskite Composite Nanofibers

“…Such pleasing features have empowered this evolving class of materials to be applied in the light-emitting diodes, light-emitting transistors, and photomemories in addition to the light-harvesting-related applications. [14] Reports from several authors have indicated the following interesting achievements; drastic increase in the PCE from 3.8% in 2009, [15] to 23.7% in a period of 10 years, a remarkable improvement in stability from a few hours of operation to a maximum life time of 1 year [16] and beyond, broadened range of materials including flexible and cheap substances and a notable reduction in production costs due to the ease of assembling methods. [17] However, due to the numerous advantages associated with the fiber geometry such as the light weight, increased flexibility, and the ease of conversion into other structures such as fabrics, together with an increasing demand for textile-based energy-harvesting devices, developed with the intent of powering in body, on body, near body, and other wearable electronics, [18][19][20] the research in the domain of fiber-shaped solar cells is slowly following the footsteps of their 2D counterparts.…”

Robust Hydrophobic and Hydrophilic Polymer Fibers Sensitized by Inorganic and Hybrid Lead Halide Perovskite Nanocrystal Emitters

“…Realization of practical LHP NC emitters is critically dependent upon improving their structural, thermodynamical, and optical stability under ambient conditions, which remains the foremost challenge for such nanomaterials (Huang et al, 2017; Kovalenko et al, 2017; Akkerman et al, 2018; Zhao et al, 2018). Encapsulation of perovskite NCs into macro- or nanoscale polymeric structures has been recently demonstrated (Huang et al, 2016; Raja et al, 2016; Wang et al, 2016, 2017; Hou et al, 2017; Lu et al, 2017; Ma et al, 2017; Murphy et al, 2017; Demkiv et al, 2018; Liao et al, 2018; Lin et al, 2018; Sygletou et al, 2018; Tsai et al, 2018; Wong et al, 2018; Xin et al, 2018; Yang M. et al, 2018; Yang S. et al, 2018; Zhang et al, 2018; Zhu et al, 2018) as simple and low-cost methodologies to preserve the LHP NC chemical integrity by suppressing water and oxygen transmission, improving the thermal stability, and reducing structural modifications, to which LHP NCs are highly susceptible, such as ligand desorption and nanocrystal sintering. Furthermore, integration of the NCs into polymers provides a method to improve their solid-state processability into films, microspheres, fibers, or more complex composites while offering new functionalities such as polarizing PL (Raja et al, 2016; Lu et al, 2017), light detection (Wang et al, 2016), biological labeling and sensing (Wang et al, 2017; Zhu et al, 2018) or device applications such as light emitting diodes (Huang et al, 2016; Liao et al, 2018; Lin et al, 2018; Tsai et al, 2018; Xin et al, 2018; Yang M. et al, 2018; Zhang et al, 2018; Zhu et al, 2018).…”

“…Electrospinning allows for a simple, cost-effective and industrially scalable fabrication of long and continuous polymer fibers (Persano et al, 2013; Yu et al, 2017; Savva and Krasia-Christoforou, 2018), enabling the incorporation of a variety of inorganic nanoparticles and thus generating functional nanocomposites (Chronakis, 2015). Fiber composite emitters appear particularly attractive for optoelectronics bearing unique properties such as tolerance to extremely small bending radii and large tensile strains while preserving the structural integrity and bright emission of the perovskite NCs (Wang et al, 2016, 2017; Murphy et al, 2017; Liao et al, 2018; Lin et al, 2018; Tsai et al, 2018; Yang M. et al, 2018). In particular, enhanced water/optical (Wang et al, 2016, 2017; Murphy et al, 2017; Liao et al, 2018; Lin et al, 2018; Tsai et al, 2018; Yang M. et al, 2018) and thermal (Liao et al, 2018) stabilities have been demonstrated upon nanocrystal encapsulation into polymer fibers.…”

Electrospun Ag-doped SnO2 hollow nanofibers with high antibacterial activity

“…Furthermore, in the preparation of composite nanomaterials, multiple preparation methods have been used, such as the absorption method, hydrothermal method, solvothermal method, and sol-gel method. In particular, the one-step method is a simple and fast synthesis method [12]. As a doping antimicrobial agent, silver has been demonstrated to have excellent antimicrobial activity and very insignificant changes in the mechanical properties of the material [13].…”