液晶网络是由液晶聚合物单体适度交联得到，兼具有聚合物的弹性和液晶的各向异性，包括多刺激响应能力、可逆的驱动以及可编程的形状变形等性能，因此具有良好的外场响应性、分子协同作用和弹性。氧化石墨烯膜层具有优秀的光热转换性能，而光具有环保性、远程可控性等优异的特性，因此光致形变的氧化石墨烯/液晶网络（GO-LCNs）复合膜逐渐成为人们的研究热点。它可以制作柔性机器人、仿生光热驱动器等先进器件，具有良好的发展前景。本文在两种厚度的液晶网络膜上制作氧化石墨烯薄膜，构成氧化石墨烯/液晶网络复合膜，测量了温度或红外光作用下液晶网络膜厚度对其响应性能的影响。本文结果为复合膜的应用设计提供了实验基础，并以此为基础设计了GO-LCNs复合膜的仿生器件。

二维材料具有高折射率和高透光率等优异光学特性，利用激光加工氧化石墨烯材料，会发生还原反应并生成具有类石墨烯材料特性的还原氧化石墨烯，这使得基于氧化石墨烯材料设计菲涅耳透镜成为可能。相较于传统的光学透镜及微型光学透镜，这一设计将透镜的尺寸从厘米级缩减到纳米级。针对工作波长532 nm设计了基于氧化石墨烯薄膜的菲涅耳透镜，通过瑞利–索末菲衍射理论及电磁场数值仿真测试了菲涅耳透镜的聚焦效果，并且通过滴铸法制备了氧化石墨烯薄膜（约500 nm），在薄膜上用激光加工菲涅耳透镜，最终得到透镜聚焦光斑直径2.14 μm，聚焦效率41.2%。相比旋涂法制备氧化石墨烯薄膜，滴铸法制备氧化石墨烯具有效率高、价格低廉的优点。该设计为纳米级的基于氧化石墨烯的光学系统的集成化和大规模生产提供了可能。

介绍了一种利用飞秒激光技术制备的石墨烯异质结薄膜晶体管（GHTFT）。基于还原氧化石墨烯制备石墨烯的原理，该晶体管利用飞秒激光直接在硅基底上制备石墨烯，最终获得了3.05×10²的电流开关比。相较于以前报道的石墨烯晶体管，该值提升了10²。同时还研究了不同还原程度的氧化石墨烯对GHTFT电流开关比的影响，结果表明氧化石墨烯的还原程度越高，GHTFT的电流开关比越大，这说明飞秒激光能够有效调节GHTFT的电学性能。除此之外，鉴于当前石墨烯制备的困难，提出的方法能够有效避免转移过程和化学过程，同时飞秒激光的高效率提高了石墨烯晶体管的制备效率。

In this study, three-dimensional porous magnesium ferrite/titanium dioxide/reduced graphene oxide (MgFe₂O₄-GM/TiO₂/rGO (MGTG)) was successfully synthesized via green and hydrothermal-supported co-precipitation methods using the extract of Garcinia mangostana (G. mangostana) as a reducing agent. The characterization results indicate the successful formation of the nano/micro MgFe₂O₄ (MFO) and TiO₂ on the structure of the reduced graphene oxide (rGO), which can also act as efficient support, alleviating the agglomeration of the nano/micro MFO and TiO₂. The synergic effects of the adsorption and photodegradation activity of the material were investigated according to the removal of crystal violet (CV) under ultraviolet light. The effects of catalyst dosage, CV concentration, and pH on the CV removal efficiency of the MGTG were also investigated. According to the results, the CV photodegradation of the MGTG-200 corresponded to the pseudo-first-order kinetic model. The reusability of the material after 10 cycles also showed a removal efficiency of 92%. This happened because the materials can easily be recollected using external magnets. In addition, according to the effects of different free radicals ·O₂^?, h⁺, and ·OH on the photodegradation process, the photocatalysis mechanism of the MGTG was also thoroughly suggested. The antibacterial efficiency of the MGTG was also evaluated according to the inhibition of the Gram-positive bacteria strain Staphylococcus aureus (S. aureus). Concurrently, the antibacterial mechanism of the fabricated material was also proposed. These results confirm that the prepared material can be potentially employed in a wide range of applications, including wastewater treatment and antibacterial activity.

Surface-enhanced Raman scattering (SERS) substrates based on chemical mechanism (CM) have received widespread attentions for the stable and repeatable signal output due to their excellent chemical stability, uniform molecular adsorption and controllable molecular orientation. However, it remains huge challenges to achieve the optimal SERS signal for diverse molecules with different band structures on the same substrate. Herein, we demonstrate a graphene oxide (GO) energy band regulation strategy through ferroelectric polarization to facilitate the charge transfer process for improving SERS activity. The Fermi level (E_f) of GO can be flexibly manipulated by adjusting the ferroelectric polarization direction or the temperature of the ferroelectric substrate. Experimentally, kelvin probe force microscopy (KPFM) is employed to quantitatively analyze the E_f of GO. Theoretically, the density functional theory calculations are also performed to verify the proposed modulation mechanism. Consequently, the SERS response of probe molecules with different band structures (R6G, CV, MB, PNTP) can be improved through polarization direction or temperature changes without the necessity to redesign the SERS substrate. This work provides a novel insight into the SERS substrate design based on CM and is expected to be applied to other two-dimensional materials.

单结太阳电池的能量转换效率从根本上受限于Shockley-Queisser(S-Q)理论极限, 二端叠层结构可同时解决单结器件中面临的光谱失配和热弛豫能量损耗问题, 是突破S-Q极限最有前途的实用技术。二端叠层太阳电池中的复合层作为中间层的重要组分, 为来自两侧的电子和空穴提供复合位点, 避免了电荷堆积造成的开路电压损失并促进了电流流通, 是实现高性能叠层器件的关键因素之一。理想的复合层应具有较高电导率以提高电荷复合速率、高光学透过率以保证后结子电池的有效光吸收、良好的化学稳定性以降低溶剂对子电池的溶解伤害以及较低的制备成本以推动叠层电池的商业化生产进程。目前已有多种材料被应用于二端叠层太阳电池中, 如薄金属、透明导电氧化物、导电聚合物、氧化石墨烯等, 在钙钛矿-钙钛矿、钙钛矿-有机、钙钛矿-晶硅叠层器件中发挥了重要作用。本文归纳了不同类型叠层太阳电池复合层的研究进展, 系统介绍了复合层的种类、设计原则、制备工艺等, 对比其优缺点并提出了复合层目前存在的问题和面临的挑战, 为制备高效叠层电池提供了有益参考。

光子筛不受衍射极限限制且设计结构灵活，是一种新型衍射元件。相比于振幅型光子筛，相位型光子筛能量透过率更高，成像对比度更加尖锐，具有应用优势。然而，常见衍射光学器件面临加工复杂及难以调制等局限。石墨烯及其衍生材料具有良好的光电调制特性，被广泛用于衍射光学器件制备。利用激光直写技术可实现诱导还原氧化石墨烯，是一种简单高效的微纳加工技术。利用时域有限差分方法研究光子筛的衍射特性，并基于激光直写技术制备氧化石墨烯光子筛。通过不同激光功率加工可获得材料的折射率调制，器件实现了明显的焦距调制(1.62 mm)和聚焦效率的提高(13.6%)。该方法有望为实现可调制衍射光学元件提供简便、灵活的设计与制备手段。