论文标题
H2O冰的热解吸：从纳米级膜到散装
Thermal Desorption of H2O-Ice: From Nanoscale Films to the Bulk
论文作者
论文摘要
已经使用石英 - 晶体微平衡（QCM）和温度填充的解吸研究研究了从53纳米到101微米的H2O膜的解吸。观察到属于无定形的固体水（ASW），堆叠无序的冰I（ICE ISD）和六边形冰I（ICE IH）的三个解吸阶段。 ASW的解吸仅在> 10微米膜中可见，并且与ICE I解吸10-15 K分开，并且相关的解吸能为64 kJ mol-1。正如文献中所指出的那样，发现53纳米膜的解吸能接近50 kJ mol-1，但是随着膜厚度的增加，冰的解吸能I升高，直到达到65-70 kJ mol-1的高原。提高解吸能增加的原因是由于分子由于H2O的覆盖层而无法解吸的，因此无法解吸。在对100毫米薄膜发生的冰I完全解吸冰I之前，使用QCM观察到在200 k附近的10和20微米膜的QCM时观察到一个两阶段的冰I。该事件对应于从92-260 k处在92-260 k供热后收集到的X射线衍射模式的冰ISD，以使冰ISD恢复。由于ASW的结晶导致了文献中通常所述的立方冰。因此，ICE是ASW初始结晶产物的正确术语。
Desorption of H2O films ranging from 53 nanometres to 101 micrometre thicknesses have been investigated using a quartz-crystal microbalance (QCM) and temperature-programmed desorption. Three desorption stages are observed belonging to amorphous solid water (ASW), stacking disordered ice I (ice Isd), and hexagonal ice I (ice Ih). The desorption of ASW is only visible for the >10 micrometre films and is separated from the ice I desorption by 10-15 K and has an associated desorption energy of 64 kJ mol-1. The desorption energy of the 53 nanometre film was found to be near 50 kJ mol-1 as also noted in the literature, but with increasing film thickness the desorption energy of ice I rises until reaching a plateau around 65-70 kJ mol-1. The reason for the increased desorption energy is suggested to be due to molecules unable to desorb due to the thick covering layer of H2O and possibly re-adsorption. Before complete desorption of ice I which occurs around 220 K for the 100 micrometre film, a two-stage ice I desorption is observed with the QCM for the 10 and 20 micrometre films near 200 K. This event corresponds to the desorption of ice Isd as corroborated by X-ray diffraction patterns collected upon heating from 92-260 K at ambient pressure. Cubic ice is not observed as is commonly stated in the literature as resulting from the crystallisation of ASW. Therefore, ice Isd is the correct terminology for the initial crystallisation product of ASW.
