Investigating the chemical sensitivity of melting in zeolitic imidazolate frameworks.
Investigating the chemical sensitivity of melting in zeolitic imidazolate frameworks.
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研究咪唑沸石骨架中熔化的化学敏感性。
DOI：
10.1039/d2dt02142k
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Bumstead AM
中科院分区：
文献类型：
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作者：
Bumstead AM
形成熔融淬火玻璃的沸石咪唑酯骨架（ZIF）的数量仍然有限，其中大多数显示cag网络拓扑结构。在这里，我们将我们的研究扩展到zni拓扑结构ZIF，在改变其连接体化学之前，通过引入2-甲基咪唑和5-氨基苯并咪唑，从ZIF-zni [Zn（Im）2]开始。发现ZIF-zni熔化并形成玻璃，Tm = 576 °C且Tg = 322 °C，但不可能制备没有氧化锌杂质的玻璃。向该结构中加入2-甲基咪唑酯得到ZIF-61 [Zn（Im）1.35（mIm）0.65]，其分解而不通过液态。然而，掺入少量的5-氨基苯并咪唑酯导致ZIF [Zn（Im）1.995（abIm）0.005]具有比纯ZIF-zni更低的熔融温度（Tm = 569 °C），并且没有氧化锌生长的证据。这证明了ZIF中的解链行为对接头化学的敏感性，仅0.25%的变化能够引起解链温度的7 °C变化。这项研究突出了ZIF熔化的化学敏感性，并作为一个有前途的策略，调整其熔化行为。
The number of zeolitic imidazolate frameworks (ZIFs) that form melt-quenched glasses remains limited, with most displaying the cag network topology. Here, we expand our studies to zni topology ZIFs, starting with ZIF-zni [Zn(Im)2] before changing its linker chemistry, by incorporating 2-methylimidazolate and 5-aminobenzimidazolate. ZIF-zni was found to melt and form a glass, with Tm = 576 °C and Tg = 322 °C, although it was not possible to prepare the glass without zinc oxide impurities. The addition of 2-methylimidazolate to the structure gave ZIF-61 [Zn(Im)1.35(mIm)0.65], which decomposed without passing through the liquid state. However, incorporating small quantities of 5-aminobenzimidazolate resulted in a ZIF [Zn(Im)1.995(abIm)0.005] with a lower melting temperature (Tm = 569 °C) than pure ZIF-zni, and no evidence of zinc oxide growth. This demonstrates the sensitivity of melting behaviour in ZIFs towards linker chemistry, with only a 0.25% variation capable of eliciting a 7 °C change in melting temperature. This study highlights the chemical sensitivity of melting in ZIFs and serves as a promising strategy for tuning their melting behaviour.