Scalable Direct Writing of Lanthanide-Doped KMnF₃ Perovskite Nanowires into Aligned Arrays with Polarized Up-Conversion Emission

Abstract

The use of one-dimensional nano- and microstructured semiconductor and lanthanide materials is attractive for polarized-light-emission studies. Up-conversion emission from single-nanorod or anisotropic nanoparticles with a degree of polarization has also been discussed. However, microscale arrays of nanoparticles, especially well-aligned one-dimensional nanostructures as well as their up-conversion polarization characterization, have not been investigated yet. Herein, we present a novel and facile paradigm for preparing highly aligned arrays of lanthanide-doped KMnF (KMnF:Ln) perovskite nanowires, which are good candidates for polarized up-conversion emission studies. These perovskite nanowires, with a width of 10 nm and length of a few micrometers, are formed through the oriented attachment of KMnF:Ln nanocubes along the [001] direction. By the employment of KMnF:Ln nanowire gel as nanoink, a direct-writing method is developed to obtain diverse types of aligned patterns from the nanoscale to the wafer scale. Up-conversion emissions from the highly aligned nanowire arrays are polarized along the array direction with a polarization degree up to 60%. Taking advantage of microscopic nanowire arrays, these polarized up-conversion emissions should offer potential applications in light or information transportation.

Design of Layer‐Structured KAlF4:Yb/Er for Pressure‐Enhanced Upconversion Luminescence

“…To further address this challenge, we have identified Yb 3+ /Er 3+ ‐doped KAlF 4 microsheets, with octahedral corner‐sharing layered structure and relatively smaller elastic constant in the [001] direction than that of the [100] or [010] . KAlF 4 has similar crystal structure as previously reported inorganic upconversion host materials KX(Mn, Mg, Zn)F 3 , the difference is that the F‐atoms between AlF 6 octahedral sheets in the [001] direction are combined by a weak interaction with potassium ions coordinated between the interlayers, rather than shared as above‐described . This might make KAlF 4 a more suitable candidate to tolerate high pressure than analogs with different crystallographic structures, such as organic crystals, organic–inorganic hybrid perovskites, and other materials with brittle frameworks .…”

Engineered Anisotropic Fluids of Rare‐Earth Nanomaterials

“…Generally, nanoparticles with an anisotropic shape (one-dimensional nanorods or two-dimensional nanodiscs) would show unique polarization-dependent luminescent properties. [32][33][34] The inherent nematic ordering in the nanomaterials could facilitate the alignment of anisotropic nanoparticles and the achievement of polarization-dependent excitation of their photoluminescence. To demonstrate this, we investigated the polarization-dependent excitation of the down-shifting emissions of b-NaYF 4 :5 %Eu 3+ nanorods (Figure 4) and the upconversion emissions of b-NaYF 4 :20 %Yb 3+ ,2 %Er 3+ nanorods (Supporting Information, Figure S9).…”

“…The ordered microstructures of the solvent‐free TLCs based on RE nanoparticles could generate novel collective properties that are different from discrete or bulk materials. Generally, nanoparticles with an anisotropic shape (one‐dimensional nanorods or two‐dimensional nanodiscs) would show unique polarization‐dependent luminescent properties . The inherent nematic ordering in the nanomaterials could facilitate the alignment of anisotropic nanoparticles and the achievement of polarization‐dependent excitation of their photoluminescence.…”

Progress of controllable synthesis of rare-earth containing perovskite nano-materials

“…对于卤化物型稀土钙钛矿纳米材料而言, 氯化物 和溴化物1D纳米材料较为少见, 而氟化物1D纳米材料 报道较多 [29,31] . 通过热分解法和共沉淀法都可制备氟 化物1D纳米材料, 以金属三氟乙酸盐为前驱体, 在高 图 6 (a, b) CsYbI 3 纳米晶的TEM图像及晶格傅里叶变换得 到的衍射花样, 纳米晶的粒径分布图 [34] .…”