Tailoring surface features and pore structure by carbon spiral fibers to construct the high-strength carbon foams for the fast and cyclic photo-thermal oil absorption

Two key limitations affecting the commercial application of carbon foams for fast clean-up of varied oils are the complex synthesis process and poor mechanical stability.In this work,an effective method is reported to fabricate the efficient oil-absorbing materials(CSF@MCF)of carbon spiral fibers(CSFs)anchored on melamine carbon foam(MCF)with superior mechanical properties and excellent photothermal con-version.The interwoven CSFs can not only provide extra rigidity but also reduce the stress concentration of the carbon skeleton,which greatly improves the mechanical properties with 6.3 times maximum compression stress and 4.5 times ultimate tensile strength than MCF.In addition,the pure carbon component can reduce the interface resistance and excite the free electrons more easily,thus realizing high-efficiency photothermal conversion in a wide range of wavelengths.Under light irradiation,the CSF@MCF can be quickly heated up to 70℃and achieve ultra-high absorption of crude oil,up to 62 g g_(-1),due to its low density and large absorption volume.Meanwhile,the CSF@MCF exhibits impressive absorption stability with persistent superhydrophobicity and a high recovery efficiency of over 85%.Superadding its simple preparation process,low production cost,and excellent acid-alkali resistance,the CSF@MCF shows great commercial potential for effectively absorbing varied oils.

Controllable coating NiAl-layered double hydroxides on carbon nanofibers as anticorrosive microwave absorbers

For harsh real-world service settings,it is essential to build corrosion-resistant,diverse,and effective microwave absorbers.Herein,we successfully prepared a 3D NiAl-layered double hydroxide/carbon nanofibers(NiAl-LDH/CNFs)composite material as an anticorrosive microwave absorber assisted by an atomic layer deposition(ALD)method.The size,coating thickness,and content of NiAl-LDH can be readily adjusted by changing the ALD cycling numbers.The optimized NiAl-LDH/CNFs demonstrates prominent microwave absorbing properties including the strongest reflection loss of–55.65 dB and the widest effective absorption bandwidth of 4.80 GHz with only 15 wt%loading.The reasons for performance improvement are the cooperative effect of interfacial polarization loss,conduction loss,and three-dimensional porous structure.Moreover,due to the synergistic effects between the excellent impermeability of CNFs and the trapping ability of NiAl-LDH for chloride ions,NiAl-LDH/CNFs exhibits strong corrosion resistances under acidic,neutral,and alkaline conditions.NiAl-LDH/CNFs should be a potential candidate to simultaneously use for microwave absorption and corrosion resistance,and this work provides a certain guiding significance for designing microwave absorbers that satisfy the corrosion resistance.

High densities of magnetic nanoparticles supported on graphene fabricated by atomic layer deposition and their use as efficient synergistic microwave absorbers

一个原子层免职(ALD ) 方法被采用了综合 Fe < 潜水艇 class= “ a-plus-plus ” > 3 O < 潜水艇 class= “ a-plus-plus ” > 4 /graphene 和 Ni/graphene composites。吸收同样准备的 composites 的性质的结构和微波被调查。graphene 的表面被 Fe 浓密地盖住 < 潜水艇 class= “ a-plus-plus ” > 3 O < 潜水艇 class= “ a-plus-plus ” > 没有重要团块或大空缺，有狭窄的尺寸分布的 4 或 Ni nanoparticles，和磁性的 nanoparticles 在每张 graphene 表上是很好分布式的。涂的 graphene 材料展览显著地改善了电磁(他们) 与太古的 graphene 相比的吸收性质。最佳的思考损失( RL )为 Fe 与仅仅 1.4 公里的厚度在 15.6 GHz 到达 46.4 dB <潜水艇class=“ a-plus-plus ”> 3 O <潜水艇class=“ a-plus-plus ”>使用 100 获得的 4 /graphene composites Fe 骑车<潜水艇class=“ a-plus-plus “> 2 O <潜水艇class=” a-plus-plus “> 3 免职由氢减小列在后面。提高的吸收能力从匹配的有效阻抗产生，从增加的磁性的成分的多重界面的极化和增加的磁性的损失。而且与另外的最近报导的材料相比， composites 有更低的充满比率和导致显著地增加的他们吸收性质的更小的涂层厚度。这证明由 ALD 的 graphene 上的磁性的粒子的那 nanoscale 表面修正是设计小、高效率的微波吸收器的一个很有希望的方法。

Rationally tailoring interface characteristics of ZnO/amorphous carbon/graphene for heat-conduction microwave absorbers

With the increasingly severe electromagnetic interference issue and the huge heat dissipation demand caused by the miniaturized and integrated electronic devices,exploring the heat-conduction microwave absorption(MA)materials is highly desired and remains a great challenge.Herein,we reported the fabrication of ZnO/amorphous carbon(ZnO/AC)hybrid films covered on the surface of graphene(ZnO/AC/Graphene)to simultaneously apply as the MA and thermal management materials.The ZnO/AC coatings synthesized with the auxiliary of an atomic layer deposition(ALD)method are highly uniform and controllable,which can significantly improve the MA performance and thermal conduction properties of graphene.The reflection loss(RL)of−55.4 dB and the effective absorption bandwidth of 5.3 GHz were achieved with thickness of 2.0 mm for ZnO/AC/Graphene at a low loading content(3 wt.%).The minimum RL of−57.9 dB can be obtained in the ZnO/AC/Graphene composites at a low frequency(7.8 GHz).Moreover,the absorption frequency can be regulated by changing the ZnO/AC which can be readily implemented by adjusting the ALD cycles of ZnO.The thermal conductivity of ZnO/AC/Graphene is up to 257.8 mW·m^(−1)·K^(−1),increased by 53.2%compared with natural rubber.The enhancement mechanisms of microwave loss and heat conduction are systematically studied in detail.This work not only develops an excellent candidate,but also provides a novel strategy to design functional materials for heat-conduction MA application.