fig4

Figure 4. (A) Grown process of Cs₃Cu₂I₅ and CsCu₂I₃ SCs with pressure-assisted cooling method; (B and C) SEM images of Cs₃Cu₂I₅ and CsCu₂I₃ SCs grown with pressure-assisted; (D) EL spectra of the WLEDs under various driving voltages; (E) frequency response of the WLEDs. Inset is the captured eye diagram. Reproduced with permission: under a Creative Commons Attribution License^[42]. SEM: scanning electron microscopy; SC: single crystal; EL: electroluminescence; WLED: white light-emitting diode.