Tailor-Made Host-Guest Organic-Inorganic Hybrid Antimony Halide Enables Efficient Light-Emitting Diodes.

Organic-inorganic antimony (Sb) halides are garnering increasing interest for lead-free perovskite light-emitting diodes (LEDs), but the non-radiative recombination and poor charge transport are hard-treat case to restrict their electroluminescent performance. Here we developed efficient Sb halide LEDs based on the tailor-made host-guest (PhP)SbCl (PhP = tetraphenylphosphonium) emitters that enable good luminescence and charge transport properties simultaneously. Experimental and theoretical studies reveal that the self-trapped excitons triggered by excited-state structural deformation were localized in spatial-confined [SbCl] polyhedrons, generating a high photoluminescence quantum yield (96.

Efficient Orange Light-Emitting Diodes from Nontoxic Organic-Inorganic Hybrid Copper Halides Enabled by Nonionic Surfactant Chemisorption.

Ternary copper halides with an eco-friendly property have emerged as attractive candidates to replace toxic lead-containing perovskites for light-emitting diodes (LEDs), yet achieving long-wavelength electroluminescence remains unexplored. Herein, we report the first realization of orange-emitting LEDs (595 nm) based on nontoxic organic-inorganic PEACuI (PEA = β-phenylethylamine) films enabled by a nonionic surfactant poly(propylene glycol) bis(2-aminopropyl ether) (APPG) chemisorption. Experimental and theoretical analyses rationalize that the APPG additive has strong chemisorption with the Cu-I framework within the grain boundaries of PEACuI films, which not only improves the film's morphology but also passivates the iodine vacancy defects.

Efficient Deep-Blue Light-Emitting Diodes from Highly Luminescent Eu-Doped Alkali Metal Halide Nanocrystals via Lattice Field Modulation.

Lead-halide perovskite nanocrystals (NCs) are promising for fabricating deep-blue (<460 nm) light-emitting diodes (LEDs), but their development is plagued by low electroluminescent performance and lead toxicity. Herein, the synthesis of 12 kinds of highly luminescent and eco-friendly deep-blue europium (Eu)-doped alkali-metal halides (AX:Eu; A = Na, K, Rb, Cs; X = Cl, Br, I) NCs is reported. Through adjustment of the coordination environment, efficient deep-blue emission from Eu-5 → Eu-4 transitions is realized.

Efficient Large-Area (81 cm) Ternary Copper Halides Light-Emitting Diodes with External Quantum Efficiency Exceeding 13% via Host-Guest Strategy.

Ternary copper (Cu) halides are promising candidates for replacing toxic lead halides in the field of perovskite light-emitting diodes (LEDs) toward practical applications. However, the electroluminescent performance of Cu halide-based LEDs remains a great challenge due to the presence of serious nonradiative recombination and inefficient charge transport in Cu halide emitters. Here, the rational design of host-guest [dppb]CuI (dppb denotes 1,2-bis[diphenylphosphino]benzene) emitters and its utility in fabricating efficient Cu halide-based green LEDs that show a high external quantum efficiency (EQE) of 13.

Deep-blue narrow-band emissive cesium europium bromide perovskite nanocrystals with record high emission efficiency for wide-color-gamut backlight displays.

Lead halide perovskite nanocrystals (NCs) are highly promising for backlighting display applications due to their high photoluminescence quantum yields (PLQYs) and wide color gamut values. However, the practical applications of blue emitters are limited due to the toxicity of lead, unstable structure, and unsatisfactory PLQY. Herein, we report the successful synthesis of divalent europium-based perovskite CsEuBr NCs using a modified hot injection method.

Recent Advances and Opportunities of Eco-Friendly Ternary Copper Halides: A New Superstar in Optoelectronic Applications.

Recently, the newly-emerging lead-free metal-halide materials with less toxicity and superior optoelectronic properties have received wide attention as the safer and potentially more robust alternatives to lead-based perovskite counterparts. Among them, ternary copper halides (TCHs) have become a vital group due to their unique features, including abundant structural diversity, ease of synthesis, unprecedented optoelectronic properties, high abundance, and low cost. Although the recent efforts in this field have made certain progresses, some scientific and technological issues still remain unresolved.