退役锂离子电池正极材料直接回收的研究现状和展望

随着全球各国大力发展新能源汽车产业,以锂离子电池（LIBs）为主的动力电池数量急剧增长。然而,LIBs的使用寿命有限,早期装机的LIBs在近几年已达到其退役要求。大量的退役电池亟需有效地回收处理,否则会对环境和人类造成危害,同时导致贵金属资源的流失。传统的电池回收技术以火法和湿法回收为主,能够实现对退役LIBs各种成分的精细化回收及再利用,但通常污染大、能耗高、回收周期长。因此,亟需开发绿色、节能、高效的LIBs回收技术。近年来,新兴的电池材料直接回收技术因工艺简单、碳排放少、能耗低、回收周期短等优势而备受关注。综述了目前主流的正极材料直接回收技术及其优缺点,分析了其在低成本、低能耗等方面的贡献,并对正极材料的功能化及LIBs闭环回收的最新进展做了介绍。最后,展望了退役LIBs正极材料及其他组分回收再利用的前景和发展趋势,旨在为电池回收领域研究提供参考。     

HPMo@UiO-66-SO3H用于中碳链结构磷脂的高效合成

以四氯化锆、磷钼酸水合物、1,2,4,5-苯四甲酸和（3-巯基丙基）三甲氧基硅烷为原料,通过原位合成法及接枝共聚法制得负载磷钼酸的磺酸基功能化UiO-66（HPMo@UiO-66-SO3H）。采用XRD、FTIR、SEM、EDS、XPS、N2吸附-脱附和TG-DTG对其进行了结构表征;应用HPMo@UiO-66-SO3H促进大豆卵磷脂与中碳链脂肪酸（辛酸和癸酸）酯交换合成富含辛酸和癸酸的中碳链结构磷脂,通过正交实验优化了反应条件,并对比了HPMo@UiO-66-SO3H与HPMo、UiO-66、HPMo@UiO-66和UiO-66-SO3H的反应活性,考察了HPMo@UiO-66-SO3H的循环利用性。结果表明,HPMo@UiO-66-SO3H具有介孔结构,并含有大量HPMo和磺酸基活性组分,且组分间可显著协同促进中碳链结构磷脂的合成反应;当HPMo@UiO-66-SO3H含量为大豆卵磷脂、辛酸和癸酸总质量的百分之5,m（大豆卵磷脂）∶m（辛酸）∶m（癸酸）=1∶10∶10,50 ℃下反应4 h时,产物的中碳链脂肪酸接入率高达百分之94.31（辛酸和癸酸接入率分别为百分之44.21和百分之50.10）;HPMo@UiO-66-SO3H可循环利用5次活性无明显下降。提出了HPMo@UiO-66-SO3H促进酯交换制备中碳链结构磷脂过程的可能反应机理。     

共改性煤粉增强丁苯橡胶的硫化、力学和热稳定性能研究

将硅烷偶联剂KH⁃560和硫化促进剂CZ共改性煤粉（Coal）作为增强填料加入到丁苯橡胶（SBR）中制备改性SBR/ Coal复合材料,通过设置不同的共改性Coal的添加量,寻找KH⁃560、CZ共改性Coal增强丁苯橡胶的最佳实验配比。结果表明,KH⁃560的最佳添加量为Coal质量的5 %,此时SBR/ Coal⁃KH560复合材料的力学性能最佳; KH⁃560和CZ改性Coal可以明显减少Coal团聚现象,在丁苯橡胶中均匀分散。当Coal⁃KH560⁃CZ添加量为40 %时,与纯SBR相比,拉伸强度由1.66 MPa升高至2.9 MPa,断裂伸长率由295 %升高至390 %,撕裂强度由7.1 N/mm增加至11.6 N/mm,复合材料的力学性能和热稳定性能得到改善,加工性能也得到较大提升。     

激光雷达料位计在水泥厂料仓监测中的应用

水泥工厂料仓的料位监测中,由于物料粒径小且多采用空气和提升机输送,输送过程中料仓内粉尘大且存在物料粘附或结块的可能,导致难以对其料位做出精确、稳定的监测。激光雷达料位计基于W频段雷达电磁波的测量原理,具有体积小、安装调试简单、配置灵活、精度高等优点; 用激光雷达料位监测技术可有效实现对其料仓中料位安全、稳定、可靠的实时监测,准确的料位监测和料位报警控制还可以有效地防止“冒仓”事故的发生。     

Evaluation of the effect of high-speed sintering on the mechanical and crystallographic properties of dental zirconia sintered bodies

There are only a few reports investigating the effects of high-speed sintering on the properties of dental zirconia. In this study, we investigated the effects of high-speed sintering on the crystal phase, mechanical properties, microstructure, and LTD resistance of 3 mol. % and 4 mol. % Y₂O₃ stabilized zirconia (3Y and 4Y zirconia). In both 3Y and 4Y zirconia, yttria distribution in the zirconia sintered body was suppressed and the LTD resistance was improved by high-speed sintering. High-speed sintering slightly reduced the mechanical properties of 3Y and 4Y zirconia, but they showed clinically sufficient mechanical properties. From the above results, it was concluded that high-speed sintered 3Y and 4Y zirconia are sufficiently clinically acceptable.     

Configuration and characters of novel Li2TiO3 tritium breeder cubic units with tuned channel structure via lithography-based 3D printing

Li₂TiO₃ is regarded as a vital tritium breeder candidate due to its favorable properties in Helium-Cooled Pebble Bed. However, the point contact stress breakage for traditional pebble structure can cause the blocking of tritium recovery system, and seriously reduce the safety and tritium self-sufficiency ability of fusion reactor. For addressing above problems, in this paper, complex-shaped Li₂TiO₃ cubic units were manufactured firstly via lithography-based 3D printing. According to the principle of tritium transport, the cubic unit structures with ordered channels were built and evaluated by finite element analysis. The photocuring parameters were optimized to improve printing accuracy by establishing an overgrowth model. After optimizing the sintering schedule, the Li₂TiO₃ cubic units with excellent relative density (92.3%TD) and packing factor (80.99%) were yielded, and it also had an outstanding compressive strength (84.4 MPa). The results of thermal cycling test shown that the Li₂TiO₃ cubic units possessed a prominent thermal cyclic durability.     

SiCnw@SiC foam prepared based on vapor-solid mechanism for efficient microwave absorption

A SiC_nw@SiC foam with highly efficient microwave absorption (MA) performance was successfully synthesized based on Vapor-Solid (V–S) growth mechanism. SiC nanowire (SiC_nw) and SiC foam skeleton efficiently form a double network coupling structure, which gives additional interface polarization and dielectric loss for the SiC foam, significantly enhancing the MA capacity of the foam. In this study, the SiC_nw@SiC foam has a minimum reflection loss (RL_min) of ?86.31 dB and an effective absorption bandwidth (EAB) of 12.55 GHz in room-temperature environment. However, the MA performance of SiC_nw@SiC foam decreases with increasing temperature, which may be due to the thickening of the SiO₂ layer in the SiC_nw at high temperature. At 600 °C, it has no effective absorption bandwidth, while at 1000 °C, the EAB and RL_min were 0.6 GHz and ?13.04 dB, respectively. As the temperature reaches 1000 °C, the defects in the material further increase, leading to a recovery in the MA performance.     

Improving performance of proton ceramic electrolysis cell perovskite anode by Zn doping

As an important renewable energy, hydrogen energy becomes an important part of the future energy system. Proton ceramic electrolysis cell (PCEC) enables the efficient, clean, large-scale preparation of hydrogen, which is a new type of energy conversion device, attracting the attention of many researchers. Sr₂Fe_1.4Zn_0.1Mo_0.5O_6-δ (SFZM) anode materials were developed to investigate the effect of B-site doping of Zn on the electrochemical properties of the Sr₂Fe_1.5Mo_0.5O_6-δ (SFM) materials. The results reveal that the doping of Zn increases the concentration of oxygen vacancies and improves the electrocatalytic activity, which in turn improves the performance of the material. A current density of 408 mA cm⁻² has been achieved at 1.3 V when the SFZM-based single cell was operated in an electrolysis mode (50% H₂O in air) at 600 °C, higher than SFM-based single cells (286 mA cm⁻² at 1.3 V). In addition, the SFZM-based single cell exhibited good durability in a stability test at an electrolysis current density of 408 mA cm⁻². This work confirms that SFZM is a promising material for proton ceramic electrolysis cell anode.     

Monatomic Sb thin films alloyed with Sb2S3 enables superior thermal stability and resistance drift by spontaneous self-decomposition

Monatomic Sb thin films can eliminate the risks of compositional partitioning, but it normally crystallizes instantly and fails to maintain amorphous state at room temperature. Here, we prepared Sb_x (Sb₂S₃)_100-x thin films. The materials consist of pure Sb with low resistance drift and chalcogenide Sb₂S₃ with high thermal stability. It is found that the Sb_64·8(Sb₂S₃)_35.2 thin film possesses the advantages of these two compounds. The thin film showed good phase-change ability with an ultralow resistance drift coefficient of 0.006, much lower than conventional Ge₂Sb₂Te₅ (0.076). Moreover, it also exhibited a better amorphous thermal stability. These improvements are closely related to the hybrid nanostructure of Sb crystals and Sb–S phase by spontaneous self-decomposition in the Sb-rich Sb–S material. Our work thus demonstrates that the binary Sb-rich Sb–S thin film can become a promising alternative to replace the conventional Ge₂Sb₂Te₅ thin film with potential for neuromorphic synaptic devices.     

High temperature oxidation behavior of porous MoAlB ceramic from 800 °C to 1100 °C in air

MoAlB possesses the characteristics of both metals and ceramic materials, which has attracted extensive attention due to its excellent high-temperature oxidation resistance. For this reason, porous MoAlB is considered applicable to the practice of filtration under harsh environment. In this study, the high-temperature oxidation behavior of porous MoAlB ceramics is systematically studied at the temperatures ranging from 800 to 1100 °C. According to the results, the porous MoAlB exhibits good oxidation resistance at a maximum temperature of 1000 °C. The oxidation kinetics of porous MoAlB can be divided into three stages, and the estimated activation energies of the three stages are 253.83 kJ·mol⁻¹, 367.48 kJ·mol⁻¹ and 317.84 kJ·mol⁻¹, respectively. In the stable stage at 1000 °C, the quadratic mass gain per unit area shows linearity over time, and the oxidation rate of porous MoAlB reaches 37.31 mg²·cm⁻⁴·h⁻¹. As revealed by the analysis of the composition and microstructure of oxide layers, the main components of the oxide layer include MoO₃, MoO₂, Al₂O₃, B₂O₃. With the extension of oxidation time, the content of Al₂O₃ in the oxide films increases. The average pore size, permeability and open pore porosity of porous MoAlB show a trend of first decreasing and then tending to be stable. In addition, a discussion is conducted on the high-temperature oxidation mechanism of porous MoAlB.