Cs₂SnCl₆: To Emit or to Catalyze? Te⁴⁺ Ion Calls the Shots

Abstract

A low concentration of Te4+ doping is found to be capable of endowing the lead‐free Cs2SnCl6 perovskites with excellent photoluminescence quantum yield (PLQY), while further increasing Te4+ concentration leads to PLQY deterioration. The mechanism behind the improved PLQY is intensively studied and reported elsewhere. However, little work is conducted to understand the decreased PLQY at high doping levels and to explore its implications for non‐PL‐related applications. Here, it is demonstrated that the Te4+‐incorporated Cs2SnCl6 can be promising candidate for efficient CO2 photocatalysis. An optimum photocatalytic performance is achieved when Te4+ concentration reaches as high as 50%, at which point significant PL quenching has occurred. Through a detailed spectral characterization, such concentration‐dependent functionality is attributed to systematic changes in both electronic and local crystal structure, which allow a robust regulation of excitation energy relaxation channels. These findings expand the scope of available photocatalysts for CO2 reduction and also inform synthetic planning for the preparation of multifunctional Pb‐free metal halide perovskites.

Spectral Tunability, Luminescence Enhancement, and Temperature Sensitivity of Sb3+-Doped Bismuth-Based Halide Emission Crystals for Anti-Counterfeiting Applications

“…The PL intensity gradually increases as the Sb concentration increases from 1% to 12%. However, beyond this range, a concentration quenching effect occurs, leading to reduced emission intensity. , A similar trend is observed for RBC: x %Sb excited at 305 nm, as indicated in Figure S6.…”

“…The maximum emission peak occurs at 12%Sb doping concentration. Beyond this concentration, a phenomenon known as quenching is observed, where the emission intensity decreases due to concentration-related effects. , The similar behavior of these two systems might be indicative of certain structural or electronic characteristics shared between the two compounds.…”

“…Beyond this concentration, a phenomenon known as quenching is observed, where the emission intensity decreases due to concentration-related effects. 9,28 The similar behavior of these two systems might be indicative of certain structural or electronic characteristics shared between the two compounds. The lifetime decay curves depicted in Figures 2e,f provide insights into the radiative processes.…”

Sb3+–doped 0D Cs3GdCl6 microcrystals with a near-unity photoluminescence quantum yield and high thermal quenching resistance for light-emitting application

“…All-inorganic lead-free luminescent metal halides doped with main-group ns 2 -electron ions (e.g., Sn 2+ , Sb 3+ , Bi 3+ , and Te 4+ ) have recently evoked reviving interest in the community of materials science owing to their superior optical properties and great prospects for various optoelectronic applications. [1][2][3][4][5][6][7][8] In contrast to the d-and f-electron dopants such as Mn 2+ , Cr 3+ , and rare-earth ions, which exhibit low absorption and emission chemical route at low temperatures remains a challenge, because rare-earth halides tend to crystallize into the hydrated phase in solution, [38][39][40] which may quench the PL due to the presence of the high-energy vibrational -OH group. In this regard, it is of fundamental significance to develop a new approach for the wet-chemical synthesis of ns 2 -electron ion doped Cs 3 RECl 6 crystals to facilitate efficient and tunable PL coupled with excellent thermal quenching resistance for device engineering in practical applications.…”

“…, Sn 2+ , Sb 3+ , Bi 3+ , and Te 4+ ) have recently evoked reviving interest in the community of materials science owing to their superior optical properties and great prospects for various optoelectronic applications. 1–8 In contrast to the d- and f-electron dopants such as Mn 2+ , Cr 3+ , and rare-earth ions, which exhibit low absorption and emission efficiencies due to the parity-forbidden d → d and f → f transitions, the main-group s-electron ions have a significantly larger absorption coefficient resulting from the allowed s → p transitions. 9–17 Therefore, s-electron dopants can serve as both sensitizers and activators in a variety of luminescent materials, facilitating precise customization of their optical absorption and emission properties.…”