γ-Al2O3法制备复合多孔树脂及其调湿与甲醛吸附性能

复合多孔树脂以其调湿速度快、湿含量高等特点比传统多孔硅胶更适合作为智能调湿材料。本文利用氢氧化铝高温分解产生活性氧化铝并释放水蒸气的致孔途径制备出复合多孔树脂。通过TG、SEM、 FTIR、XRD和氮气吸附等手段表征了该树脂的形貌和结构特征,测试了复合多孔树脂分别在高湿和低湿环境的调湿性能和饱和湿含量,讨论了多孔树脂在不同温度条件的调湿性能和在25℃时对微量甲醛的吸附性能。结果表明：本文的致孔方法能有效地使树脂内部形成多孔结构。复合多孔树脂具有良好的调湿和甲醛吸附性能。在制备过程中通过控制树脂内部的孔参数,材料能将空间相对湿度在4h内调控并维持在50%-60%的范围之内,且不受温度变化的影响,甲醛吸附量为5.55ppm/g。材料可以作为智能调湿材料用于文物保护,为文物存放环境创造一个恒湿干净的空间。     

钛基多孔HA/SiO2复合涂层的制备及性能研究

为了制得表面多孔且与基材结合强度高的羟基磷灰石(HA)涂层,实验中以正丁醇为分散介质,以SiO2粉末为添加剂,纯钛片为基材,电泳沉积制备羟基磷灰石/二氧化硅/壳聚糖/(HA/SiO2/CS)复合涂层,经后续热处理得到多孔HA/SiO2复合涂层,采用扫描电镜(SEM)、傅立叶红外光谱仪(FT-IR)、X射线衍射仪(XRD)、万能材料试验机对涂层的表面形貌、组成、结构和结合强度进行测试和表征,并通过模拟体液(SBF)浸泡法对复合涂层的生物活性进行评价.结果表明:当悬浮液中的HA/SiO2/CS质量比为1∶1∶1时,制得的HA/SiO2/CS涂层经700℃热处理后获得的HA/SiO2复合涂层孔洞分布均匀,大孔孔径在10～15μm,小孔孔径在1～5μm;涂层与基材的结合强度达到25.5 MPa;多孔HA/SiO2复合涂层在SBF中浸泡7 d后,涂层表面碳磷灰石化;说明实验中添加SiO2所制得的多孔HA/SiO2复合涂层与钛基材结合强度高,且具有良好的生物活性.     

Porous Si/C composite as anode materials for high-performance rechargeable lithium-ion battery

A novel porous silicon was synthesized through a magnesiothermic reduction method of molecular sieve for the first time, the porous silicon was used as anode material, which shows a high initial specific capacity of 2018.5 mAh/g with current density of 0.1 A/g.     

高温下自生压力原位碳化制取介孔碳

以不同配比表面活性剂为软模板合成as-SBA-15, 将其在特制高压釜内, 通过高温自生压力反应(RAPET)使表面活性剂软模板在SBA-15的孔道内原位碳化, 得到碳/介孔二氧化硅复合物, 表面活性剂同时作为模板剂和碳源. 用氢氧化钠溶液腐蚀二氧化硅后得到多孔碳. 氮气吸附脱附测试结果表明, 所得到的碳材料具有较高的比表面积和较窄的孔径分布. 在氮气氛围下煅烧as-SBA-15可使表面活性剂模板挥发.     

Synthesis of highly porous zinc–carbon composites based on modified pine wood

Highly porous materials containing zinc oxide were prepared form modified pine wood. The growth dynamics of zinc oxide microcrystallites in the course of carbonization of pine sawdust mixed with ZnCl₂ was studied. The hexagonal wurtzite-type ZnO phase is formed at 400°С and is broken down at approximately 800°С. The synthesized composite material has a high specific surface area, up to 1900 m² g^–1. The relationships of the porous structure formation in the composite in relation to the temperature and subsequent treatment with water were revealed. Opening of the porous structure of the composite in the course of carbonization of modified pine sawdust is associated with the formation of crystal-like phases of carbon and ZnO.     

Nano-structured phosphorus composite as high-capacity anode materials for lithium batteries

More than LiP service: The adsorption of red phosphorus into porous carbon provides a composite anode material for lithium-ion batteries. The amorphous nano phosphorus, in the carbon matrix, shows highly reversible lithium storage with high coulombic efficiencies and stable cycling capacity of 750?mAh per gram composite.     

氮掺杂石墨烯量子点/MOF衍生多孔碳纳米片构筑高性能超级电容器

首先采用溶液法在碳布上生长Co-MOF二维纳米片,通过高温退火和刻蚀后得到MOF衍生多孔碳纳米片。以Co-MOF衍生的多孔碳纳米片/碳布(CNS/CC)作为碳基骨架,采用电化学沉积法负载高活性氮掺杂石墨烯量子点(N-GQDs),制备得到分级多孔结构的N-GQD/CNS/CC复合材料。组装成自支撑且无粘结剂的N-GQD/CNS/CC电极,当电流密度为1 A·g~(-1)时,其比电容高达423 F·g~(-1)。通过储能机制和电容贡献机制的研究表明,在碳纤维上原位生长的具有高双电层电容的CNS和表面负载具有高赝电容的N-GQDs之间相互协同作用,使得N-GQD/CNS/CC电极具有高电容性能,是一种理想的超级电容器电极材料。电极材料的高导电、分级多孔结构有利于电子的传输和电解质离子的扩散,具有良好的动力学性能,能快速充放电和具有优异的倍率特性。将电极组装成对称型超级电容器,功率密度为250 W·kg~(-1)时对应的能量密度达到7.9 Wh·kg~(-1),且经过10 000次循环后电容保持率为91.2%,说明氮掺杂石墨烯量子点/MOF衍生多孔碳纳米片复合材料是一种电化学性能稳定的具有高电容性能的全碳电极材料。     

氮杂碳原位包覆Cu2O/Co3O4@C异质结构复合材料的设计构筑及高效储锂性能

通过液相法合成了Cu₂O纳米立方体, 并在其基础上利用金属有机框架化合物(MOFs)的自组装形貌调控, 进一步构建了层级多孔Co₃O₄和氮杂碳双壳层的Cu₂O/Co₃O₄@C异质结构复合材料. 利用X射线衍射(XRD)、 扫描电子显微镜(SEM)、 透射电子显微镜(TEM)、 热重分析(TGA)、 BET比表面积及孔径分析、 拉曼光谱和X射线光电子能谱(XPS)等表征手段证实了Cu₂O/Co₃O₄@C异质结构复合材料的成功构筑. 双壳层结构设计和丰富的层级孔道结构有效抑制了材料在充放电循环过程中的体积膨胀, 材料在循环100次后仍保持了原有的形貌和构造. 表面多孔结构对电解液的充分浸润、 异质结构的界面内建电场以及缺陷氮杂碳的表面包覆有效提升了材料的电子和离子导电能力. 异质结构设计、 形貌调控、 多孔特性和氮杂碳的协同作用, 使得Cu₂O/Co₃O₄@C复合材料呈现出优异的电化学性能, 在0.1 A/g电流密度下的首次放电比容量达到2065 mA·h/g, 在 2 A/g电流密度下的可逆放电比容量高于360 mA·h/g, 在1 A/g电流密度下循环350次后仍有530 mA·h/g的高可逆放电比容量.     

Hydrothermal Synthesis of Porous Al2O3/Al Metal Ceramics: II. Mechanism of Formation of a Porous Al(OH)3/Al Composite

The formation of a porous layer of aluminum hydroxide on the surface of aluminum particles and the aggregation of Al(OH)₃/Al composite particles were analyzed theoretically. It was found that the diffusion mass transfer of the hydroxo complexes of aluminum through the porous structure of a growing layer of aluminum hydroxide to the outer surface is a rate-limiting step in the synthesis of the porous composite. A model mechanism of formation of the porous composite was developed, and rate equations were derived for describing the growth of an aluminum hydroxide layer on the surface of an aluminum particle and changes in the degree of aluminum conversion and the contact radius between composite particles. Based on the developed mathematical model and experimental data, the diffusion coefficient of the hydroxo complexes of aluminum in the porous structure of aluminum hydroxide was calculated.     

Hierarchical porous carbon/selenium composites derived from abandoned paper cup as Li-Se battery cathodes

Paper cup composed of crude cellulose is a common waste in daily life. In this paper, hierarchical porous carbons have been successfully prepared by an initial hydrothermal treatment and subsequent activation route from abandoned paper cup, and then paper cup derived carbons are used as scaffolds to fabricate serial carbon/Se composites. The optimal composite presents unique 3D porous structure, with amorphous selenium uniformly confined into the micropores of carbon. As the cathode materials of Li-Se battery, this composite reveals an initial reversible discharge capacity of 517.2 mAh g⁻¹ at 0.2C, and a capacity value of 431.9 mAh g⁻¹ can be retained after 60 cycles. Even at a high rate of 4C, a capacity value of 295.8 mAh g⁻¹ can be obtained. By comparison, the improved electrochemical performance of the optimal composite should be attributed to reasonable porous structure and effective encapsulation of amorphous selenium.     

Ultralight,High Capacitance,Mechanically Strong Graphene-Cellulose Aerogels

With increasing energy demand driving the need for eco-friendly and efficient energy storage technology, supercapacitors are becoming increasingly prevalent in wearable devices because of their portability and stability. The performance of these supercapacitors is highly dependent on the choice of electrode material. The high capacitance and mechanical properties needed for these materials can be achieved by combining graphene’s stable electrical properties with renewable cellulose’s excellent mechanical properties into porous aerogels. In this study, graphene-cellulose hydrogels were prepared by a one-step hydrothermal method, with porous, ultra-light, and mechanically strong graphene-cellulose aerogels then prepared by freeze-drying. These composite aerogels possess excellent mechanical strength and high specific capacitance, capable of bearing about 1095 times the pressure of their own weight. Electrochemical tests show the specific capacitance of these composite aerogels can reach 202 F/g at a scanning rate of 5 mA/cm². In view of their high surface area and fast charge transport provided by their 3D porous structure, graphene-cellulose aerogels have great potential as sustainable supercapacitor electrodes.     

Porous Ni/NiO nanohybrids for electrochemical catalytic glucose oxidation

The remarkable development of nanotechnology and nanoscience has greatly promoted the vigorous development of the field of nanomaterials. This study explores a porous cuboid Ni/NiO composite nanomaterial obtained by calcining NiC_2O_4·2H_2O under a N_2 environment. The composite affords direct electrochemical activity and good electrocatalytic properties. Compared to uncalcined precursor, the porous Ni/Ni O obtained after calcination exhibited higher catalytic activity for glucose oxidation with higher sensitivity. Moreover, because of its regular cube structure the as-synthesized Ni/Ni O exhibited improved electrochemical stability. Such porous Ni/Ni O nanocubes represent promising glucose catalyst with high sensitivity and selectivity, improved stability and fast amperometric response.     

New composite membranes based on crosslinked poly(acrylic acid) and porous polyethylene films

A process for the preparation of new composite membranes via free-radical copolymerization of acrylic acid with a macromolecular crosslinker (allyloxyethylcellulose) on the surface of porous polyethylene films was proposed. To reveal the effect of the porous matrix on the properties of the composites, homogeneous hydrogel membranes based on crosslinked poly(acrylic acid) were studied. The swelling ratio and transport characteristics of the membranes during separation of ethanol-water mixture by pervaporation were determined depending on the ethanol concentration. It was found that all membranes at low ethanol concentrations (0–30 vol %) exhibited high swelling ratios, which drastically decreased in the range 30–40 vol % as a result of gel collapse. The composite membranes had a higher selectivity for water over a broad range of ethanol concentrations than homogeneous membranes, but a lower flux. It was found that the strength and elasticity of porous matrices was retained in the composite membranes, which became mechanically more isotropic owing to the presence of the crosslinked component.     

电沉积多孔复合Ni-P/LaNi5电极及其析氢电催化性能

采用复合电沉积制备了Ni-P/(LaNi₅+Al) 复合镀层, 然后将镀层浸泡在浓碱液中除铝, 成功得到多孔复合Ni-P/LaNi₅电极. 通过扫描电镜(SEM)、能谱分析(EDS)和X射线衍射(XRD)仪等技术表征了电极的表面形貌、组成和相结构. 运用电化学线性伏安扫描(LSV)、恒电位电解、电化学阻抗谱(EIS)等手段研究了电极在20%(w) NaOH溶液中的析氢反应(HER)电催化性和稳定性. 结果表明, 与多孔Ni-P 电极相比, 多孔复合Ni-P/LaNi₅电极具有低的析氢过电位、高的比表面积和高的稳定性能; 多孔Ni-P/LaNi₅电极的析氢反应的表观活化自由能为35.44 kJ·mol^-1, 低于多孔Ni-P 的值(50.91 kJ·mol^-1).     

Porous nanocubic Mn(3)O(4)-Co(3)O(4) composites and their application as electrochemical supercapacitors

A simple approach has been developed to fabricate ideal supercapacitors based on porous Mn(3)O(4)-Co(3)O(4) nanocubic composite electrodes. We can easily obtain porous corner-truncated nanocubic Mn(3)O(4)-Co(3)O(4) composite nanomaterials without any subsequent complicated workup procedure for the removal of a hard template, seed or by using a soft template. In such a composite, the porous Mn(3)O(4)-Co(3)O(4) enables a fast and reversible redox reaction to improve the specific capacitance. The porous nanocubic Mn(3)O(4)-Co(3)O(4) composite electrode can effectively transport electrolytes and shorten the ion diffusion path, which offers excellent electrochemical performance. These results suggest that such porous Mn(3)O(4)-Co(3)O(4) composite nanocubes are very promising for next generation high-performance supercapacitors.     

Characteristics and Application of Porous Ceramic/Agarose Composite Beads Derived as an Affinity Medium

Porous ceramic/agarose composite beads were derived as a kind of glutathione S-transferase (GST) affinity medium to investigate the characteristics and application in fast protein liquid chromatography. The analysis of back pressure and chromatographic performance in a packed bed indicated that this kind of affinity medium with a rigid structure and a high level of column efficiency would be suitable for protein chromatography under high flow velocity. The good physical stability evidenced under harsh alkaline treatments ensured the application in real chromatography processes. When the porous ceramic/agarose composite beads were used in the purification process of fusion protein GST-ADAM15, the purity of the total GST related protein reached more than 91.6 % and the yield reached 44.6 % even at the flow velocity of 764.3 cm h^?1. The works indicated the characteristics of porous ceramic/agarose composite beads and their potential application in protein purification processes.     

纳米锡/硬碳复合材料作为嵌锂负极的研究

利用金属铁和钴纳米颗粒的催化活化作用,制备了多孔硬碳球.应用聚焦离子束切割技术,观察到扩孔后的硬碳球中充满彼此连通的发达中孔.在此多孔硬碳球中填入纳米锡(Sn)颗粒,对复合材料的电化学性能进行了测试.     

Pomegranate‐Structured Silica/Sulfur Composite Cathodes for High‐Performance Lithium–Sulfur Batteries

Porous materials have many structural advantages for energy storage and conversion devices such as rechargeable batteries, supercapacitors, and fuel cells. When applied as a host material in lithium‐sulfur batteries, porous silica materials with a pomegranate‐like architecture can not only act as a buffer matrix for accommodating a large volume change of sulfur, but also suppress the polysulfide shuttle effect. The porous silica/sulfur composite cathodes exhibit excellent electrochemical performances including a high specific capacity of 1450 mA h g^?1, a reversible capacity of 82.9 % after 100 cycles at a rate of C/2 (1 C=1672 mA g^?1) and an extended cyclability over 300 cycles at 1 C‐rate. Furthermore, the high polysulfide adsorption property of porous silica has been proven by ex‐situ analyses, showing a relationship between the surface area of silica and polysulfide adsorption ability. In particular, the modified porous silica/sulfur composite cathode, which is treated by a deep‐lithiation process in the first discharge step, exhibits a highly reversible capacity of 94.5 % at 1C‐rate after 300 cycles owing to a formation of lithiated‐silica frames and stable solid‐electrolyte‐interphase layers.     

百香果皮基原位氮掺杂多孔碳/硫复合正极的制备及储锂性能

以生物质百香果皮为碳源,KHCO₃为活化剂,采用同步活化碳化方法制备原位氮掺杂的分级多孔碳材料,将其与单质硫复合制得多孔碳/硫正极材料。通过X射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）等表征技术对制备材料的物相组成、微观形貌、比表面积及孔结构进行研究分析。同时,利用紫外可见吸收光谱研究了多孔碳对多硫化物的吸附作用,用恒电流充放电测试了不同硫含量（60%~80%）的多孔碳/硫复合正极材料的电化学性能。结果表明,制得的多孔碳材料为无定型,具有1 093 m²·g^-1的高比表面积和0.63 cm³·g^-1的孔容;丰富的多孔结构和原位氮掺杂对多硫化物的物理化学协同吸附作用,有效降低了锂硫电池的“穿梭效应”,提高了电池的放电比容量和循环性能。硫含量为60%的多孔碳/硫复合材料,在0.05C和0.2C倍率下可释放1 057.7和763.4 mAh·g^-1的高初始放电比容量,在1C的高倍率下循环300次后的保持率为75%。     

Preparation and characterization of NiP amorphous alloy/ceramic composite membrane

The NiP amorphous alloy/ceramic composite membrane of high selectivity and permeability for hydrogen was prepared by a new technique of partial electroless plating. Its permeability and ideal separation factor for H₂/Ar were investigated. The results demonstrated that the permeability of the NiP amorphous alloy membrane was almost the same as that of a porous inorganic membrane, but the separation factor for H₂/Ar through the NiP membrane was obviously higher than that through a porous inorganic one. The morphology and microstructure of NiP amorphous alloy/ceramic composite membrane were characterized by SEM and XRD.