论文标题
h $ _2 $ o and co $ _2 $表面污染锂石榴石
H$_2$O and CO$_2$ Surface Contamination of the Lithium-Stuffed Garnet
论文作者
论文摘要
了解无处不在的分子对复杂氧化物的反应性对能量应用和催化具有广泛的影响。石榴石型李$ _7 $ la $ _3 $ zr $ _2 $ _2 $ o $ _ {12} $是锂（li）-ion电池的有前途的固态电解质，并且在暴露于周围空气时，它很容易对H $ _2 $ O和CO $ _2 $做出反应。这种反应形成了李$ _7 $ la $ _3 $ zr $ _2 $ o $ $ $ _ {12} $的污染层，这对电池操作有害。 Li $ _7 $ LA $ _3 $ zr $ _2 $ o $ o $ _ {12} $与H $ _2 $ o和co $ _2 $的强烈交互，但是，让Li $ _7 $ _7 $ la $ _3 $ _3 $ zr $ _2 $ _2 $ _ $ _ {12} $ a {12）在这里，使用第一原则计算，我们研究了li $ _7 $ la $ _3 $ _3 $ zr $ _2 $ _2 $ o $ o $ _ {12} $表面上H $ _2 $ o和co $ _2 $的吸附和反应。我们表明，h $ _2 $ o通过质子和李$^{+} $的交换并产生金属氢氧化物种做出反应。在高h $ _2 $ o覆盖范围下，h $ _2 $ o分子的一半分离，而另一半保持完整。 CO $ _2 $与Li $ _7 $ LA $ _3 $ ZR $ _2 $ o $ o $ _ {12} $表面直接反应，直接生产碳酸盐物种。我们澄清说，H $ _2 $ O和CO $ _2 $与Li $ _7 $ la $ la $ _3 $ _3 $ zr $ _2 $ _2 $ o $ _ {12} $的个别反应比H $ _2 $ o和co $ $ _2 $的共同吸附更热情地吸收。最后，我们证明了低温和高压力促进了H $ _2 $ O和CO $ _2 $与Li $ _7 $ la $ la $ _3 $ _3 $ zr $ _2 $ _2 $ o $ $ _ {12} $的反应。对于储能应用，李$ _7 $ la $ _3 $ zr $ _2 $ o $ $ _ {12} $，我们的学习指南处理条件以最大程度地减少表面污染。从催化的角度来看，我们的发现揭示了使用复杂的氧化物的潜力，例如Li $ _7 $ LA $ _3 $ ZR $ _2 $ _2 $ o $ $ _ {12} $作为支持需要H $ _2 $ O分离的反应，并强大的CO $ _2 $ ADSORTINT。
Understanding the reactivity of ubiquitous molecules on complex oxides has broad impacts in energy applications and catalysis. The garnet-type Li$_7$La$_3$Zr$_2$O$_{12}$ is a promising solid-state electrolyte for lithium(Li)-ion batteries, and it readily reacts with H$_2$O and CO$_2$ when exposed to ambient air. Such reactions form a contamination layer on Li$_7$La$_3$Zr$_2$O$_{12}$ that is detrimental to the battery operations. The strong interactions of Li$_7$La$_3$Zr$_2$O$_{12}$ with H$_2$O and CO$_2$, however, make Li$_7$La$_3$Zr$_2$O$_{12}$ a promising support to catalyze H$_2$O dissociation and CO$_2$ adsorption. Here, using first-principles calculations, we investigate the adsorption and reactions of H$_2$O and CO$_2$ on a Li$_7$La$_3$Zr$_2$O$_{12}$ surface. We show that H$_2$O reacts through the exchange of proton and Li$^{+}$ and produces metal hydroxide species. At high H$_2$O coverage, half of the H$_2$O molecules dissociate while the other half remain intact. CO$_2$ reacts with the Li$_7$La$_3$Zr$_2$O$_{12}$ surface directly to produce carbonate species. We clarify that the individual reactions of H$_2$O and CO$_2$ with Li$_7$La$_3$Zr$_2$O$_{12}$ are more thermodynamically favorable than the co-adsorption of H$_2$O and CO$_2$. Finally, we demonstrate that low temperature and high partial pressure promote the reactions of H$_2$O and CO$_2$ with Li$_7$La$_3$Zr$_2$O$_{12}$. For energy storage application of Li$_7$La$_3$Zr$_2$O$_{12}$, our study guides processing conditions to minimize surface contamination. From a catalysis point of view, our findings reveal the potential of using complex oxides, such as Li$_7$La$_3$Zr$_2$O$_{12}$ as a support for reactions requiring H$_2$O dissociation and strong CO$_2$ adsorption.
