多孔炭载聚钴酞菁修饰电极用于苯二酚的电催化及检测

以二氧化硅纳米球为模板,通过葡萄糖的水热聚合反应制备了具有三维结构的多孔炭(PC)。采用电化学聚合方法将单体钴酞菁聚合在多孔炭修饰的玻碳电极(PC/GC)表面,制备了多孔炭载聚钴酞菁的修饰电极(Co-TAPc/PC/GC)。通过循环伏安法(CV)研究了间苯二酚、邻苯二酚和对苯二酚在此修饰电极的电化学响应。结果表明,相对于裸玻碳电极、多孔炭或聚钴酞菁单独修饰的电极,该修饰电极对3种同分异构体的酚类物质均有更好的电催化活性。利用计时安培技术,该修饰电极对间苯二酚、邻苯二酚及对苯二酚分别在5.0×10-6～5.0×10-4 mol/L,6.0×10-6～2.5×10-4 mol/L和2.0×10-6～8.0×10-4 mol/L范围内具有较好的线性响应。此修饰电极具有制备简单、响应灵敏、稳定性好等优点。     

聚芳醚腈共聚物的合成与性能

以二卤代苯甲腈，对苯二酚，间苯二酚为原料，制备了几种不同间苯二酚／对苯二酚比的聚芳醚腈树脂。采用流涎成膜法制备了它们的薄膜。对薄膜样品进行了红外光谱分析和热分析，测定了力学性能，在扫描电子显微镜上观察了薄膜拉伸断面。     

碳化物修饰的有序介孔炭的制备及其催化肼分解性能

 以间苯二酚和甲醛为炭源, F127 (EO₁₀₆PO₇₀EO₁₀₆) 为结构导向剂, 在酸性水/乙醇溶液中引入 (NH₄)₆Mo₇O₂₄•4H₂O 或 (NH₄)₂WO₄ 溶液, 经静置自组装形成凝胶, 再于 N₂ 中焙烧即合成出金属碳化物修饰的有序介孔炭材料. 结果表明, 金属离子的种类和用量对碳化物的分散度和介孔炭的有序度影响很大. 通过控制金属离子的用量可制备出粒径为 3~5 nm 且高度分散在介孔炭骨架中的碳化物粒子. 与分步浸渍法相比, 一步法制备的碳化物具有更高的分散度和催化肼分解活性.     

对苯二酚-二(4-氧代-4-磷杂-3,5,8-三氧杂双环[2.2.2]辛基)甲酸酯的合成及表征

自1960年Verkade 等[1 ]首次合成了结构新颖的双环笼状磷酸酯以来,由于其高度对称的结构而引起人们的极大兴趣,具有生物活性的衍生物不断见诸报道[2～3 ].由于该化合物具备丰富的炭源(季戊四醇) 和酸源(磷酸),其衍生物逐渐成为无卤膨胀阻燃剂研究的热点之一.李昕等[4-5]以PEPA为中间体,合成了分子中同时具有三个笼状磷酸酯结构的化合物的三聚物(Trimer),结构对称性好,磷含量高,热稳定性和成炭性比较好.杨兴钰等[6]以PEPA为中间体,合成了8个双环笼状磷酸酯酰胺类化合物,该类化合物集酸源、炭源和气源于一体,应用于环氧树脂材料中具有良好的阻燃性.目前含有芳环结构的PEPA衍生物的合成鲜有报道.本研究课题以季戊四醇、三氯氧磷、浓硝酸、二氯亚砜和对苯二酚等为原料,合成了一种具有芳环结构、含磷量高、耐热性好、无卤等特点的PEPA衍生物对苯二酚-二(4-氧代-4-磷杂-3,5,8-三氧杂双环[2 2 2]辛基)甲酸酯.合成路线如下:1 实验部分1.     

炭化温度对模板法合成介孔炭性能的影响

以蔗糖为炭源和硅酸钠为硅源,采用原位共聚法制备了炭/氧化硅复合体,除去氧化硅得到介孔炭材料.采用N2吸附-脱附、透射电子显微镜和红外光谱对不同炭化温度获得的样品进行表征.结果表明,随着炭化温度升高,所得的介孔炭比表面积和孔容均下降,650℃ ～ 950℃的炭化温度下获得的样品BET比表面积在586m2/g ～728 m2/g之间,孔容在0.549cm3/g～0.696cm3/g之间,孔径分布5-15nm之间.经红外光谱检测所得的介孔炭样品均含有氢和氧的功能团.     

常压干燥制备酚醛树脂基炭气凝胶研究进展

以间苯二酚-甲醛为代表的酚醛树脂基炭气凝胶是一种轻质、多孔、非晶态的纳米炭材料,在催化、吸附、电化学和隔热等领域中有广阔的应用前景.但是复杂且高成本的超临界干燥工艺极大地限制了炭气凝胶的工业化制备及其应用,因此常压干燥工艺成为目前研究最为广泛的炭气凝胶制备技术之一.本文综述了酚醛树脂基炭气凝胶常压干燥制备过程的四种结构...     

径向基函数神经网络光度法同时测定苯酚、邻苯二酚、间苯二酚和对苯二酚

对吸收峰重叠严重的苯酚、邻苯二酚、间苯二酚和对苯二酚4组分体系进行研究,以径向基函数神经网络光度法建立校正模型,同时测定了水样中的苯酚、邻苯二酚、间苯二酚和对苯二酚的含量,回收率为95.7％～109.2％。     

富氮多级孔炭材料的制备及其吸附分离CO2的性能

使用新型含氮聚合物席夫碱为炭源, SBA-15为模板,通过纳米铸型法原位合成微孔-中孔-大孔串联的多级孔富氮炭材料.材料的比表面积为752 m²·g^-1,孔容0.79 cm³·g^-1; X光电子能谱分析表明炭材料中的氮含量高达7.85%(w).将所制备的多孔炭材料应用于CO₂的吸附分离,发现炭材料的微孔发挥主导作用,表面氮掺杂发挥辅助作用.在两者的协同作用下, CO₂吸附量在常压、273 K下可达97 cm³·g^-1, CO₂/N₂和CO₂/CH₄的分离比(摩尔比)分别为7.0和3.2,低压亨利吸附选择性分别为23.3和4.2.采用Toth模型对单组分平衡吸附进行拟合,并根据理想溶液吸附理论(IAST)预测双组分CO₂/N₂和CO₂/CH₄混合气体的分离选择性分别为40和18.     

介孔炭修饰玻碳电极循环伏安法测定对苯二酚

将介孔炭分散在5g.L-1壳聚糖溶液中并滴涂在玻碳电极表面,烘箱烘干后,制备了介孔炭修饰电极。采用循环伏安法研究了对苯二酚在修饰电极上的电化学行为。结果表明:对苯二酚在该修饰电极上出现了一对灵敏的氧化还原峰,其峰电流比裸玻碳电极增大了很多,据此提出了用循环伏安法测定对苯二酚的方法。对苯二酚的浓度在1.0×10-6～1.0×10-4 mol.L-1范围内与其氧化峰电流呈线性关系,检出限(3S/N)为4.0×10-7 mol.L-1。修饰电极用于模拟水样中对苯二酚的测定,回收率在95.3%～98.7%之间,测定值的相对标准偏差(n=5)在3.8%～4.2%之间。     

离子液体辅助条件下由稻壳合成超级电容器用多孔炭（英文）

本文以稻壳为碳源,以离子液体1-丁基-3-甲基咪唑六氟磷酸盐(BMIMPF_6)为模板和辅助活化剂制备了多孔炭材料(PCs).多孔炭的比表面积达1438 m~2·g~(-1),总孔容达0.75 cm~3·g~(-1).以PCs为超级电容器电极材料,6 mol·L~(-1)的KOH溶液为电解液组装成扣式电池,在0.05 A·g~(-1)的电流密度下,比电容高达256 F·g~(-1);当电流密度增大至10A·g~(-1),其比电容仍保持在211 F·g~(-1),展现出好的倍率性能.所得的多孔炭电极均表现出优异的循环稳定性.这一工作以BMIMPF_6作为模板和辅助活化剂,为合成生物质基超级电容器用多孔炭提供了一种新方法.     

酚类糖苷缀合物的合成、表征及美白活性

根据拼合原理,以对苯二酚(p-HQ)、间苯二酚(m-HQ)及邻苯二酚(o-HQ)为先导化合物,通过一侧酚羟基的苄基保护、引入溴乙酸甲酯、还原、与3种糖元偶联、脱除保护基得到9种目标化合物。 同样以3-(4-羟基苯基)-1-丙醇为起始物质,通过苄基保护、与3种糖元偶联、脱除保护基得到3种目标化合物。 通过IR、¹H NMR、¹³C NMR、HRMS等波谱分析方法对所合成的12种目标化合物进行了结构表征。 对合成的酚类糖苷缀合物进行了美白活性研究。 结果表明,化合物p-HQ-6a、m-HQ-7a、p-HQ-6b、m-HQ-6b、o-HQ-6b、p-HQ-6c、m-HQ-7c、L-3a和L-4b对酪氨酸酶有抑制作用,其中o-HQ-6b和p-HQ-6c对酪氨酸酶的抑制作用优于阳性对照物α-熊果苷。     

纳米孔炭负载 MnOx 催化剂上苯甲醇氧化反应性能

 以纳米孔炭 (NC) 为载体, 采用浸渍法制备了一系列 MnOx/NC 催化剂, 并用于以空气为氧源的苯甲醇液相氧化反应. 通过 X 射线衍射、X 射线光电子能谱、N2 吸附-脱附和 H2-程序升温还原等手段对催化剂进行了表征, 考察了催化剂中 Mn 负载量和焙烧温度, 以及反应条件等对反应性能的影响. 结果表明, 10%MnOx/NC 催化剂的活性较高, 反应 4 h 后苯甲醇转化率可达 80.4%; 明显高于活性炭负载的 MnOx 催化剂. 这主要归因于其表面存在大量高分散、且易于还原的 Mn 物种.     

Environmentally benign chitosan as precursor and reductant for synthesis of Ag/AgCl/N-doped carbon composite photocatalysts and their photocatalytic degradation performance

In this study, we reported a novel Ag/AgCl loaded N-doped carbon composite photocatalyst (Ag/AgCl/NC) which was fabricated by a facile and green method. The composite was prepared only by two simple steps. Firstly, the Ag/N-doped carbon (Ag/NC) was prepared by one-step hydrothermal treatment; during this progress the environmentally benign and renewable natural chitosan was used as not only reducer and stabilizer, but also as a nitrogen source and carbon source. Secondly, Ag/AgCl/NC composite was synthesized via in situ oxidation reaction by adding FeCl₃. The Ag/AgCl/NC composite was characterized using X-ray diffraction, transmission electronic microscopy, energy dispersive X-ray spectra, UV-visible diffused reflectance spectra, X-ray photoelectron spectroscopy and nitrogen adsorption-desorption measurements, respectively. The obtained Ag/AgCl/NC composite exhibited a superior photocatalytic activity and stability for the degradation of rhodamine B (RhB) under visible light irradiation.     

Synthesis of cobalt–nitrogen-doped mesoporous carbon from chitosan and its performance for pollutant degradation as Fenton-like catalysts

Research on Chemical Intermediates - Supported cobalt oxides on mesoporous nitrogen-doped carbon (CoxOy/NC) were prepared by a simple pyrolysis method using cobalt acetate as the cobalt source and...     

Preparation of chemically oxidized porous carbon and its adsorption of uranium(VI) from aqueous solution

The chemically oxidized porous carbon (m-a-NC) materials were prepared by oxidation and activation of N-doped carbon (NC) materials which were produced from the glucose-urea resin primary carbon. Simultaneously, the batch experiments were carried out to investigate the adsorption of U(VI) onto the m-a-NC materials. The m-a-NC materials exhibit the maximum adsorption capacity of 397 mg/g towards U(VI) at 298.15 K and pH = 4.5. The adsorption kinetics was well fitted by the pseudo-second-order kinetic model, and the adsorption isotherm was better described by the Langmuir model. The possible adsorption mechanism of the m-a-NC for U(VI) was ion-exchange and coordination.

     

锂离子电池负极材料碳氮包覆钛酸锂的制备及表征

以钛酸正四丁酯为钛源、甲酸锂为锂源、柠檬酸为碳源、脲作为氮源,采用溶胶-凝胶法制备出了氮修饰碳包覆钛酸锂(Li₄Ti₅O₁₂/NC)的复合电极材料。 借助X射线衍射仪(XRD)、X射线光电子能谱分析仪(XPS)、傅里叶变换红外光谱仪(FTIR)、热重分析仪(TGA)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对Li₄Ti₅O₁₂/NC的晶体结构、组成和形貌进行了表征分析,结果表明,所得产物是由尖晶石结构Li₄Ti₅O₁₂外围包覆NC组成。 恒电流充放电实验结果显示,碳氮包覆量为9.48% 的Li₄Ti₅O₁₂/NC材料在1C下首次放电比容量为212.9 mA·h/g,充放电循环100周后仍能保持160.1 mA·h/g的较高比容量。 碳氮包覆不会改变材料的晶型,但能有效抑制复合材料粒径增大,同时增加复合材料锂脱嵌活性位点,提高其比容量和导电性。     

Preparation of a kind of mesoporous carbon and its performance in adsorptive desulfurization

Carbon materials were prepared using mesoporous silica HMS with different pore sizes as the hard templates and water-soluble phenolic resin as the carbon source. The obtained materials were characterized by powder X-ray diffraction, transmission electron microscopy and N₂ physical adsorption, and were used in adsorptive desulfurization. It has been shown that the carbon material prepared using HMS with larger pore size (>3 nm) presented uniform wormlike mesopore of 2.3 nm and large BET surface area (1903 m²/g). The mesoporous carbon was an excellent adsorbent to remove the refractory sulfur compound in diesel, especially dibenzothiophene and 4, 6-dimethyldibenzothiophene.     

On the Role of Metals in Nitrogen‐Doped Carbon Electrocatalysts for Oxygen Reduction

The notion of metal‐free catalysts is used to refer to carbon materials modified with nonmetallic elements. However, some claimed metal‐free catalysts are prepared using metal‐containing precursors. It is highly contested that metal residues in nitrogen‐doped carbon (NC) catalysts play a crucial role in the oxygen reduction reaction (ORR). In an attempt to reconcile divergent views, a definition for truly metal‐free catalysts is proposed and the differences between NC and M‐N_x/C catalysts are discussed. Metal impurities at levels usually undetectable by techniques such as XPS, XRD, and EDX significantly promote the ORR. Poisoning tests to mask the metal ions reveal the involvement of metal residues as active sites or as modifiers of the electronic structure of the active sites in NC. The unique merits of both M‐N_x/C and NC catalysts are discussed to inspire the development of more advanced nonprecious‐metal catalysts for the ORR.     

聚苯胺膜修饰电极对儿茶酚及对苯二酚的催化氧化

研究了电化学条件下聚合生成的聚苯胺膜对儿茶酚及对苯二酚的催化氧化。实验分析了影响电催化的几个因素：聚合电位、膜厚、溶液酸度及底物浓度，同时分析和比较了聚苯胺膜对两种不同多酚类化合物的催化反应。提出电化学测试分析多酚类化合物的可能性。     

Nano‐structured Hollow Carbon Materials from a Non‐isothermal Chemical Vapor Deposition of Polyphenols

Pyrogallic acid (PG) was used as a modeling carbon source in fabricating nano‐structured hollow carbon materials (HCMs) by a chemical vapor deposition (CVD) method. We found that non‐isothermal deposition can improve the integrity of the obtained HCMs. The different pyrolyzed species from PG under varied temperatures lead to the temperature‐dependent deposition yield, graphitization degree and morphology of the HCMs. HCMs including hollow spheres of varied sizes, cubic boxes with yolk‐shell structure, nanotubes, mesoporous particles and double‐shelled fibers, were prepared by using different templates, demonstrating the universality of this strategy. The carbon source has been extended to other plant polyphenols. The abundant and renewable solid precursors for CVD method endow this strategy excellent operation safety, improved storage and transportation convenience and low cost, and would boost the production of morphology‐ and size‐controlled HCMs and their applications in the fields such as water treatment, electrode materials, adsorbent, drug delivery, and so forth.