A bulk sample of an organic-inorganic (OI) perovskite crystal of (C6H5C2H4NH3)2PbBr4 with a layered structure showing excellent luminescent properties was rapidly synthesised. The raw materials of OI crystal were impregnated into nanoporous glass having 4-nm pores and dried, obtaining a translucent sample of OI nanocrystals in glass (OIiG). An absorbance shoulder was observed at E = 3.04 eV for OIiG, which was attributed to exciton bands, and photoluminescence (PL) duration times of τ1 = 2.8 ns and τ2 = 8.6 ns were recorded for OIiG. In contrast, for a single-crystal sample, E = 2.94 eV, τ1 = 4.1 ns, τ2 = 11.0 ns. Compared to those of the single-crystal sample, the OIiG has a higher absorbance energy, and the duration time was shorter. The exciton activation energy was 195 meV for OIiG, in contrast with 121 meV for single crystal. We propose that these changes are due to the size effect because the particle size (3-4 nm in diameter) in the OIiG is close to the Bohr radius of layer-structured OI crystals.

中文翻译：

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在玻璃中快速合成量子尺寸的有机-无机钙钛矿纳米晶体。

快速合成了具有层状结构（C6H5C2H4NH3）2PbBr4的有机-无机（OI）钙钛矿晶体，并显示出优异的发光性能。将OI晶体的原材料浸渍到具有4nm孔的纳米多孔玻璃中并干燥，从而获得玻璃中的OI纳米晶体的半透明样品（OIiG）。对于OIiG，在E = 3.04 eV处观察到一个吸收峰，这归因于激子带，并且对于OIiG，光致发光（PL）持续时间为τ1= 2.8 ns和τ2= 8.6 ns。相反，对于单晶样品，E = 2.94 eV，τ1= 4.1 ns，τ2= 11.0 ns。与单晶样品相比，OIiG具有更高的吸收能，并且持续时间更短。OIiG的激子活化能为195 meV，而单晶的激子活化能为121 meV。