Energy Upconversion in Rare‐Earth‐Doped Tin‐Based Double Halo Perovskites, A₂SnCl₆ (A = K, Rb, and Cs)

Abstract

A wet chemical methodology has been developed to synthesize the undoped and rare‐earth‐doped A2SnCl6 samples (A = K, Rb, and Cs) in cubic symmetry. The double perovskite (K2PtCl6) structure of these samples was confirmed from their PXRD, SAED, FTIR, and Raman spectra. The crystallites showed octahedral morphology in the FESEM and HRTEM images. The optical band gap of undoped A2SnCl6 increased with an increase in the size of the alkali metal ion. Eu3+ and Tb3+ (5 mol‐%) doped A2SnCl6 showed intense red‐orange and green emission when excited at 380 nm. The various radiative properties of the emission bands were analyzed using the Judd‐Ofelt theory. Yb3+/Er3+ co‐doped A2SnCl6 showed multicolor upconversion under 980 nm excitation, and the emission region varied with the alkali metal. These samples show bright emission with optimum CCT and CIE coordinates, indicating that the rare‐earth‐doped A2SnCl6 samples are suitable in applications involving Near‐UV and Near‐IR excitations.

Multi-Dopant Engineering in Perovskite Cs2SnCl6: White Light Emitter and Spatially Luminescent Heterostructure

“…Among the lead-free halide perovskites, Cs 2 SnCl 6 is regarded as an excellent host with good compatibility for different dopants including Bi 3+ , Te 4+ , Sb 3+ , Ce 3+ , Eu 3+ , and Tb 3+ . − The dopant ions can induce yellow, blue, and red emission colors in Cs 2 SnCl 6 . The combination of different dopant ions might achieve a single-phase white light emitter.…”

Sn‐Ag Synergistic Effect Enhances High‐Rate Electrocatalytic CO2‐to‐Formate Conversion on Porous Poly(Ionic Liquid) Support

“…To investigate the charge distribution between different species and clarify the reaction intermediates, the in situ Raman spectroscopy technique was employed to monitor the electrolysis over PPIL 4 -Sn 5 Ag 5 . At the open circuit potential (OCP) (Figure 7a), the very intense peak at ≈305 cm −1 is ascribed to the vibration of the SnCl bond, [26] while the much weak peak at ≈710 cm −1 is assigned to the vibration of SnO bond. [26,27] Besides, the peak at 586 cm −1 is related to the Sn(IV).…”

“…At the open circuit potential (OCP) (Figure 7a), the very intense peak at ≈305 cm −1 is ascribed to the vibration of the SnCl bond, [26] while the much weak peak at ≈710 cm −1 is assigned to the vibration of SnO bond. [26,27] Besides, the peak at 586 cm −1 is related to the Sn(IV). [26,27] These results signify Sn-species exist in the form of mixed Sn(IV) chlorides (major) and oxides (minor).…”

“…[26,27] Besides, the peak at 586 cm −1 is related to the Sn(IV). [26,27] These results signify Sn-species exist in the form of mixed Sn(IV) chlorides (major) and oxides (minor). Meanwhile, the Ag-related peak is identified at 682 cm −1 , which is attributed to the vibration of the AgOH bond.…”

Strategies for high‐performance perovskite solar cells from materials, film engineering to carrier dynamics and photon management

“…For example, Chen et al 579 synthesized an upconversion single crystal of LiYF 4 :Yb 3+ /Er 3+ by using the Bridgman method, which was placed on the back of MAPbI 3 device on the path of the incident light to convert the NIR light in the ranges of 900-1000 nm and 1500-1600 nm to visible red and green light, and obtain the enhancement efficiency cells (Figure 21F). The rare earth ions can also be used to dope the perovskite 591,592 or CTMs [593][594][595] to prepare the upconversion materials. For example, Ding et al 592 introduced Yb 3+ , Tm 3+ , and Er 3+ ions into CsPbF 3 to prepare the upconversion perovskite nanocrystals.…”