Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 16
·5594-5599
·
IF 7.059
Hechun Lin,Xu Zhang,Lele Cai,Jie Lao,Ruijuan Qi,Chunhua Luo,Shiyou Chen,Hui Peng,Rong Huang,Chungang Duan
The optoelectronic application of fluorescent lead halide perovskite (LHP) nanocrystals is limited by their poor stability in humid atmosphere. However, we found that high-quality and high-stability fluorescent perovskites embedded in PbBrOH can be synthesized via the reaction of PbBr2 with MBr (M: Cs or CH3NH3+) triggered with imidazole derivatives in water. Imidazole can etch and hydrolyze the nonluminescent MPbBr3 to form high-quality fluorescent perovskites. After the perovskites are formed, a protective PbBrOH matrix grows rapidly on the surface of the perovskite nanocrystals and acts as a water-resistant layer. The embedded fluorescent perovskites can exhibit great stability even in water, heat and UV light with a PLQY of up to 30%. Density functional theory (DFT) calculations show that the enhanced stability results from the positive energy cost of the water molecule entering the lattice of PbBrOH, which is much higher than the negative value for water entering CsPbBr3; therefore, water is prevented by the PbBrOH surface from entering the embedded fluorescent perovskite. The PbBrOH surface layer has twofold beneficial effects: (i) preventing water from entering the perovskite nanocrystals, (ii) dispersing the perovskite nanocrystals in the matrix and preventing their aggregation so that highly luminescent composites can be formed. Our strategy opens a new avenue for the development of high-efficiency and high-stability fluorescent inorganic and organic perovskites.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry B
·
2023
·Vol. 11
·期 8
·1705-1712
·
IF 7
Jie Guan,Dandan Yang,Junyi Ma,Yingzhuo Shen,Qin Xu,Xiaoya Hu
The extension application of perovskites in aqueous media such as bioassays requires the development of a water-stable perovskite with a simple preparation process and low cost. However, the degradation of perovskites in aqueous solution is still a thorny problem. Here, we develop a methylimidazole-assisted two-step synthesis protocol to prepare CsPbBr3@PbBrOH nanorods with superior water stability and remarkable optical properties at room temperature. The synergy of 2-methylimidazole (2-MIM), an N-donor ligand, with water can not only facilitate CsPbBr3 formation and suppress CsPb2Br5 or Cs4PbBr6 formation, but also promote the formation of a PbBrOH shell capping CsPbBr3. 2-MIM is ionized into 2-MIM− in DMF and 2-MIM+ in water. They passivated the surface defects and changed the crystallization environment, leading to water-stable CsPbBr3@PbBrOH. The obtained CsPbBr3@PbBrOH nanorods can still maintain 91% PL intensity after being stored in water for more than 2 months. Furthermore, the CsPbBr3@PbBrOH nanorods show excellent stability in polar solvents, water, and phosphate buffer solution in a wide pH range, as well as better thermal and irradiation stability. In addition, the CsPbBr3@PbBrOH nanorods are further functionalized with polydopamine (PDA) for biomolecular immobilization and immunoassay studies. The resulting assay shows a detection limit of 0.003 ng mL−1 for IgG detection, illustrating important progress towards expanding fluorescence labeling application of perovskite nanomaterials for immunoassays.
研究领域:
材料科学
·
生物医学工程
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Yidi Wang,Yang Wang,Ziqi Wang,Liangfeng Luo,Benjamin Tawiah,Chang Liu,Jiachuan Hua,Yang Ming,John H. Xin,Wai-Yeung Wong,Bin Fei
While the metal halide perovskite materials are emerging as potentially promising photocatalysts, they still suffer from the intrinsic instability, seriously hampering their further practical applications. In this study, a perovskite-based composite with a sandwich structure is first established to realize the encapsulation of individual octylamine-capped MAPbBr 3 (OM-PE) quantum dots (QDs), and the Zeolitic Imidazolate Framework-67 (ZIF-67) isolates the individual OM-PE@PbBrOH QDs (2 nm) to preserve their unique optoelectronic properties while preventing degradation from environmental factors. The resulting sandwich composite was proved to be a staggered-gap heterostructure with a p–n junction, in which the PbBrOH layer acted as a water-resisting covering and ZIF-67 layer promoted the electron mobility. Benefiting from the chemical interactions and interfacial charge dynamics among the different layers, the OM-PE@PbBrOH ⊂ ZIF-67 composite exhibited the superior stability in water for two months, and presented an enhanced photodegradation efficiency of organic dyes (malachite green, methylene blue and rhodamine B), which is around 24 times higher than that of pristine perovskite. By integrating the respective merits of each component, this work unprecedentedly constructs the 2 nm sandwich-like OM-PE@PbBrOH ⊂ ZIF-67 composite, and opens new avenues for stable, efficient, and multifunctional photocatalytic systems, with potential applications beyond wastewater treatment.
研究领域:
材料科学
·
环境科学
·
纳米技术
·
光催化
·
无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Lifang Wu,Jun Wang,Wenzhi Wu
In this work, photoluminescence (PL) intensity and stability of CsPbBr 3 /PbBrOH powders synthesized by one-pot method are enhanced through the encapsulation of poly (vinyl acetate) (PVA) in water. Understanding the function of PbBrOH and PVA matrix for photogenerated transition can be achieved through temperature-dependent steady-state and time-resolved PL. The enhanced PL quantum yield (65.9%) and longer lifetime indicate the strengthened structural stability and a significant reduction in nonradiative recombination of CsPbBr 3 . Negative thermal quenching can be observed and interpreted using a multilevel PL transition model. Through nanosecond time-resolved PL spectra under femtosecond laser excitation, it is revealed that the PL position shows a redshift (∼8 nm) with time delay due to the reduction of band-filling effect during the recombination of photoexcited carriers. PVA further encapsulates CsPbBr 3 /PbBrOH powders to form a flexible film, which exhibits excellent thermal and water stability due to the dual protective effects of PVA and PbBrOH. The experimental investigation demonstrates that CsPbBr 3 encapsulated by PbBrOH and PVA possesses excellent luminescent and water-resistant characteristics, making it a new choice for practical applications in LEDs and screen printing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）