Conjugate electrospinning-constructed special-shaped Janus nanobelt with improved upconversion luminescence and regulable magnetism Bi-functionality

Developing multifunctional nanomaterials through the design and construction of advanced nanostructures that are highly compatible with various substances is a crucial approach. In this work, special-shaped Janus nanobelt with both up-conversion luminescence (UCL) and magnetism is firstly designed and fabricated via a conjugate electrospinning coupled with a di-crucible fluorination. [YF3: Yb3+, Ho3+@SiO2] belt-in-belt nanobelt//CoFe2O4 nanobelt conjugate electrospinning-constructed special-shaped Janus nanobelt (shorted as C-SJNB) was designed and successfully prepared for a case study. C-SJNB is composed of two mutually independent micro-zones, which are YF3: Yb3+, Ho3+@SiO2 belt-in-belt nanobelt (BNB) called as luminescent micro-zone, and CoFe2O4 magnetic nanobelt acted as magnetic micro-zone. In the C-SJNB structure, the design ensures that the luminescent substance does not directly contact with the magnetic substance, thereby reducing the adverse effects of the darkbrown magnetic CoFe2O4 on the luminescent performance. C-SJNBs with structural advantages exhibit 7 times the UCL intensity compared to counterpart luminescent-magnetic YF3: Yb3+, Ho3+/SiO2/CoFe2O4 hybrid nanobelts (HNBs) prepared by uniaxial electrospinning. Further, compared with [YF3: Yb3+, Ho3+@SiO2]// CoFe2O4 parallel electrospinning-constructed special-shaped Janus nanobelt (shorted as P-SJNB), C-SJNB possesses a higher quality of micro-morphology, and avoids the degradation of luminescence performance caused by the mixing of magnetic and luminescent substances at the interface. The UCL intensity and magnetism of CSJNBs can be adjusted by changing the content of CoFe2O4. When the CoFe2O4 content increases from 0.5 mmol to 4 mmol, the saturation magnetization of C-SJNBs increases from 4.42 to 13.94 emu & sdot;g 1. The newly established technology eliminates the needs for complex electrospinning and post-processing procedures. The formation mechanism of C-SJNBs has been established, providing technical support for synthesizing other Janus nanobelts with a belt-in-belt structure on one side. These advanced Janus nanobelts are ideal for developing poly-functional nanomaterials and have important applications in dual-mode imaging, display devices, batteries, drug loading and delivery.