Ultrastable Perovskite–Zeolite Composite Enabled by Encapsulation and In Situ Passivation

Abstract

Metal halide perovskites have been widely applied in optoelectronic fields, but their poor stability hinders their actual applications. A perovskite-zeolite composite was synthesized via in situ growth in air from aluminophosphate AlPO-5 zeolite crystals and perovskite nanocrystals. The zeolite matrix provides quantum confinement for perovskite nanocrystals, achieving efficient green emission, and it passivates the defects of perovskite by H-bonding interaction, which leads to a longer lifetime compared to bulk perovskite film. Furthermore, the AlPO-5 zeolite also acts as a protection shield and enables ultrahigh stability of perovskite nanocrystals under 150 8C heat stress, under a 15-month long-term ambient exposure, and even in water for more than 2 weeks, respectively. The strategy of in situ passivation and encapsulation for the perovskite@AlPO-5 composite was amenable to a range of perovskites, from MA-to Cs-based perovskites. Benefiting from high stability and photoluminescence performance, the composite exhibits great potential to be virtually applied in light-emitting diodes (LEDs) and backlight displays.

In situgrowth of lead-free halide perovskites into SiO2sub-microcapsules toward water-stable photocatalytic CO2reduction

“…The SiO 2 shell usually imparts better photostability to HP nanocrystals which is probably due to the suppressed migration of ions and vacancies. 46,47 The yolk-shell Cs 2 AgBiBr 6 @SiO 2 mesoporous sub-microspheres have great potential for photocatalysis in a polar solvent medium owing to their better thermal, light and water stability. The photocatalytic CO 2 reduction performance was measured in a mixed medium of acetonitrile and water under visible light irradiation (λ > 420 nm), with Co(bpy) 3 2+ (bpy = 2,2′-bipyridine) as a molecular cocatalyst and triethanolamine (TEOA) as a hole scavenger.…”

“…The SiO 2 shell usually imparts better photostability to HP nanocrystals which is probably due to the suppressed migration of ions and vacancies. 46,47…”

Chirality Transfer from Chiral Mesoporous Silica to Perovskite CsPbBr 3 Nanocrystals: The Role of Chiral Confinement

“…The elemental ratio of Pb:Br is 1:2.63 survey by XPS, which is probably caused by loss of halogen. 31 These evidences demonstrate that the CsPbBr 3 NCs distributed tightly within the CMS template.…”

“…Figure S9 shows the TRPL spectra of CsPbBr 3 film and CsPbBr 3 @CMS, the decay curves of CsPbBr 3 film and CsPbBr 3 @CMS sample can be well fitted into multiexponential and triexponential equation, slow decay and fast decay are related with the excitonic recombination and the high trap density at the crystal surface, respectively (Table S1). 31 The average lifetime (τ ave ) of CsPbBr 3 NCs elongated from 12.28 to 19.16 ns after confinement growth in CMS. This kinetics test results indicated that much lower quantity of defects and vacancies created by Pb-Br anti-site and under-coordinated Pb atoms for the CsPbBr 3 NCs within CMS matrix, and significantly suppressed the nonradiative decay of the CsPbBr 3 NCs, which are similar to previously reported the perovskite@AlPO-5 and perovskite-gel composite materials.…”

“…This kinetics test results indicated that much lower quantity of defects and vacancies created by Pb-Br anti-site and under-coordinated Pb atoms for the CsPbBr 3 NCs within CMS matrix, and significantly suppressed the nonradiative decay of the CsPbBr 3 NCs, which are similar to previously reported the perovskite@AlPO-5 and perovskite-gel composite materials. 4,31 In order to better characterize the luminous properties of the composite, we conducted a PLQY test on the CsPbBr 3 @CMS. The 13.7 % PLQY is more than twice the reported CH 3 NH 3 PbBr 3 nanoparticles grown in mesoporous silica ( 5.5 %), 33 which confirms the excellent emission performance of the CsPbBr 3 @CMS composite.…”