Bandgap-Engineered CsPbBr3xI3–3x Alloy Nanowires for Broadly Tunable Nanoscale Lasers

Halide perovskite nanowires (NWs) have excellent photoelectric properties, such as high quantum efficiency and carrier mobility, and are ideal candidates for next-generation optoelectronic devices and circuits. In particular, all-inorganic perovskite materials have a soft and dynamic crystal lattice, tunable bandgaps, better thermal stability, etc., which make them ideal candidates for wavelength-tunable emitters and full-color displays. Here, we reported an anion exchange method to synthesize bandgap-modulated CsPbBr 3 x I 3–3x alloy NWs on SiO 2 /Si substrate. These NWs have smooth end surfaces and exhibit NW lasing with a threshold of 18.09 μJ cm –2 and a high-quality factor of 633–1075. Moreover, under a 355 nm pulse laser illumination, room-temperature wavelength continuous tunable lasing ranging from 538 to 699 nm is realized using these bandgap-tunable perovskite NWs. The growth strategies of these bandgap-graded structures may offer an interesting system for enriching the synthesis methods of alloy perovskites and exploring applications in multifunctional nanophotonic and optoelectronic devices.