采用高温固相法在1 050℃下烧结，制备了LiCoO₂低浓度梯度改性样品，分别为LiF掺杂包覆（LCOLF、LCO@LF）和MgF₂掺杂包覆（LCOMF、LCO@MF）。通过光电子能谱、透射电子显微镜和电化学技术等表征方法，对比分析材料形貌及电化学性能。结果表明，体相掺杂复合电极中，LCOLF热重测试显示出最优热稳定性，LCOMF晶体中（003）和（104）晶面间距收缩；45℃下1C倍率循环70圈后，LCOLF和LCOMF比容量分别为141.45和166.98 mAh·g^-1，循环性能优于LiCoO₂。表面包覆复合电极中，LCO@LF和LCO@MF晶粒表面光洁且晶格氧键价都向更高结合能方向增强；LCO@MF构建了坚实且紧密的包覆层，循环70圈后，放电比容量和容量保持率分别为183 mAh·g^-1和91.26%（LCO@LF分别为154.38 mAh·g^-1和77.54%），循环性能显著优于体相掺杂。

制备了一系列Tb³⁺-Eu³⁺掺杂含Na_8.12Y_1.293Si₆O₁₈晶相的玻璃陶瓷，通过多种表征技术系统研究了热处理条件对其微观结构和发光性能的影响，最终确定最佳热处理条件为670 ℃、90 min。Tb³⁺的最佳掺杂浓度(物质的量分数)为0.5%，超过此浓度时会出现四极-四极相互作用主导的浓度猝灭。双掺玻璃陶瓷中存在Tb³⁺向Eu³⁺的能量传递。在293~493 K温度范围内，双掺玻璃陶瓷表现出良好的热稳定性，热猝灭活化能为0.24 eV，色度偏移为2.1×10^-2。此外，该材料具有一定的温度传感性能，最大温度灵敏度为5.7×10^-3 K^-1，热重复性比为96.6%。

Malignant tumours always threaten human health. For tumour diagnosis, positron emission tomography (PET) is the most sensitive and advanced imaging technique by radiotracers, such as radioactive ¹⁸F, ¹¹C, ⁶⁴Cu, ⁶⁸Ga, and ⁸⁹Zr. Among the radiotracers, the radioactive ¹⁸F-labelled chemical agent as PET probes plays a predominant role in monitoring, detecting, treating, and predicting tumours due to its perfect half-life. In this paper, the ¹⁸F-labelled chemical materials as PET probes are systematically summarized. First, we introduce various radionuclides of PET and elaborate on the mechanism of PET imaging. It highlights the ¹⁸F-labelled chemical agents used as PET probes, including [¹⁸F]-2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]-FDG), ¹⁸F-labelled amino acids, ¹⁸F-labelled nucleic acids, ¹⁸F-labelled receptors, 18F-labelled reporter genes, and ¹⁸F-labelled hypoxia agents. In addition, some PET probes with metal as a supplementary element are introduced briefly. Meanwhile, the ¹⁸F-labelled nanoparticles for the PET probe and the multi-modality imaging probe are summarized in detail. The approach and strategies for the fabrication of ¹⁸F-labelled PET probes are also described briefly. The future development of the PET probe is also prospected. The development and application of ¹⁸F-labelled PET probes will expand our knowledge and shed light on the diagnosis and theranostics of tumours.

本研究采用溶剂热法制备了一种具有狭缝孔结构的铝基-卟啉金属有机骨架(Al-TCPP)材料，并研究了其对电子特种气体C₃F₈的吸附分离和回收性能。所合成的Al-TCPP具有狭长平板孔结构，其孔尺寸为0.6 nm×1.1 nm，略微大于C₃F₈的分子尺寸(0.57 nm×0.52 nm)。同时，Al-TCPP孔道内密布的C—H键与μ-OH基团可与C₃F₈的F原子形成多重氢键作用位点，进一步增强了对C₃F₈的亲和力。吸附实验结果表明，在298 K、100 kPa下Al-TCPP对C₃F₈的吸附量高达96.1 cm³·g^-1，而N₂吸附量仅为6.1 cm³·g^-1，其理想选择性高达244.8，超过了目前已报道的吸附剂材料。同时，C₃F₈在低压区的吸附热为50.6 kJ·mol^-1，远高于N₂的16.5 kJ·mol^-1。密度泛函理论(DFT)计算表明，Al-TCPP结构中相邻的卟啉单元上的多个H原子可以同时与C₃F₈的多个F原子形成氢键。穿透实验证实Al-TCPP可以实现C₃F₈/N₂混合物的有效分离，并且通过脱附可以回收获得高纯度的C₃F₈。

在镍钴铝酸锂正极材料Li[Ni_0.8Co_0.15Al_0.05]O₂(NCA)制备过程中表面遗留的碱性物质会严重影响其循环稳定性能，针对这一难题，提出使用Y(PO₃)₃对其进行表面包覆改性，利用Y(PO₃)₃与表面残留的LiOH反应消除表面残碱，并探讨包覆改性对NCA整体性能的影响机制。测试分析结果表明，在低温煅烧过程中前驱体表面会形成均匀致密的Y(PO₃)₃和LiPO₃包覆层，LiPO₃有较高的离子电导率，双包覆层能够防止活性物质在电化学循环过程中与电解液相互接触时发生有害副反应，提高电极材料的循环稳定性。其中Y(PO₃)₃包覆量(质量分数)为1%的样品在0.1C下的首次库仑效率从未改性样品的78.65%提高到88.50%，在1C下循环150圈后容量保持率从59.38%提高到85.33%，相比于未改性样品具有更高的首次库仑效率和更优异的循环性能。

The electronic structure, magnetic, and optical properties of two-dimensional(2D) GaSe doped with rare earth elements X (X=Sc, Y, La, Ce, Eu) were calculated using the first-principles plane wave method based on density functional theory. The results show that intrinsic 2D GaSe is a p-type nonmagnetic semiconductor with an indirect bandgap of 2.661 1 eV. The spin-up and spin-down channels of Sc-, Y-, and La-doped 2D GaSe are symmetric, they are non-magnetic semiconductors. The magnetic moments of Ce- and Eu- doped 2D GaSe are 0.908μ_B and 7.163μ_B, which are magnetic semiconductors. Impurity energy levels appear in both spin-up and spin-down channels of Eu-doped 2D GaSe, which enhances the probability of electron transition. Compared with intrinsic 2D GaSe, the static dielectric constant of the doped 2D GaSe increases, and the polarization ability is strengthened. The absorption spectrum of the doped 2D GaSe shifts in the low-energy direction, and the red-shift phenomenon occurs, which extends the absorption spectral range. The optical reflection coefficient of the doped 2D GaSe is improved in the low energy region, and the improvement of Eu-doped 2D GaSe is the most obvious.