吸附剂的物理结构和表面性质的研究——酸处理对硅胶孔结构和吸附性能的影响

测定了样品的孔结构参数和水蒸气吸附性能。试验表明:用pH3.00酸化的自来水洗涤酸性水凝胶可制得典型的细孔硅胶;用3mol/L以上的硫酸溶液浸泡酸性水凝胶可制得平均孔半径约为300的特粗孔硅胶。     

乙酰丙酮钛螯合物掺杂丙烯酸酯共聚物水溶胶

乙酰丙酮钛螯合物掺杂丙烯酸酯共聚物水溶胶;乙酰丙酮钛螯合物; 丙烯酸酯共聚物水溶胶;掺杂     

钛掺杂对LiNi0.75Co0.25O2结构与性能的影响

应用溶胶-凝胶法合成LiNi(0.75-x)Co0.25TixO2(x=0,0.1,0.25)系列正极材料,其结构、形貌、粒度、电化学性能由TG、XRD、SEM和电池充放电测试表征研究表明,材料的电化学性能与钛掺杂量密切相关.在钴含量不变的情况下,随着Ti含量(x)的增加,材料由六方层状结构逐渐向立方结构转变,x=0.25时,出现了立方相与六方相共存.根据实验和理论计算结果简要讨论了钛掺杂对正极材料LiNi0.75Co0.25O2结构和电化学性能的影响.     

钛掺杂钙钛矿制备高效率钙钛矿太阳能电池

采用钛离子掺杂钙钛矿薄膜的方法修饰钙钛矿晶界缺陷。研究表明钛离子富集在晶界处,有效地钝化了晶界缺陷,同时有助于连续、平整、高质量薄膜的形成。经过钛离子掺杂后的钙钛矿太阳能电池电流(JSC)达到22.3 mA·cm~(-2),开路电压(VOC)达1.1 V,填充因子(FF)高达72.4%,光电转换效率(PCE)优化至17.4%,远高于未掺杂钙钛矿太阳能电池。     

硅胶负载氯掺杂二氧化钛光催化剂的水热制备与光催化活性评价

利用水热法, 以硅胶为载体, 以Ti(SO4)2为钛源, NaCl为氯源制备了具有良好性能的硅胶负载氯掺杂二氧化钛(CTS)光催化剂, 考察了氯投加量、焙烧温度及钛硅比对光催化活性的影响. 结果表明, 氯投加量为15% (nCl/nTi)、钛硅物质的量比为3:1、焙烧温度为750 ℃时制备的CTS具有最佳的光催化活性, 其比表面积为60.8 m2·g-1. CTS中的硅胶除了作为载体, 还起到了促进锐钛矿二氧化钛的生成并抑制其向金红石相转变的作用; 氯掺杂二氧化钛(CT)经硅胶负载后, 其表面孔结构发生了变化, 并且热稳定性增加. 苯酚降解实验表明, 与CT相比, CTS以0.7740 g·g-1的二氧化钛含量具有更高的光催化活性.     

聚烯丙基胺硅胶复合材料的合成及其吸附性能

氯丙基三氯硅烷-硅胶;聚烯丙基胺硅胶复合材料的合成及其吸附性能     

铕掺杂硅钛柱撑蒙脱土的合成及发光性能研究

采用溶胶凝胶法制备了Eu3+掺杂的硅钛柱撑蒙脱土(Si-Ti-MT),运用XRD,SEM-EDX和FT-IR对其结构进行了表征。结果表明,Eu3+掺杂的硅钛柱撑剂插入蒙脱土层之间,保持了蒙脱土层状结构。经荧光发射光谱和激发光谱分析可知,Si-Ti-MT是Eu3+发光的有效基体,其发射能级主要为Eu3+613 nm(5D0→7F2);激发光谱中表现了Eu3+的5个特征激发带,分别为363 nm(7F0→5D4),382 nm(7F0→5G2),395 nm(7F0→5L6),415 nm(7F0→5D1)和465 nm(7F0→5D2);热处理促进了Eu3+掺杂的硅钛柱撑蒙脱土的发光,且样品的荧光强度随着Eu3+掺杂量的增加而增强,不会发生浓度猝灭现象。     

二乙烯三胺键合硅胶的制备及其对痕量铜(Ⅱ)、镉(Ⅱ)的吸附性能研究

以二乙烯三胺为改性剂,对硅胶进行表面修饰,制备了二乙烯三胺改性硅胶吸附材料,采用傅立叶红外光谱仪(IR)对其进行表征,用静态法考察了该吸附材料对痕量铜(Ⅱ)、镉(Ⅱ)的吸附性能。在p H 5.5,35℃下恒温振荡50 min,Cu2+,Cd2+能同时被吸附材料很好的吸附,吸附的Cu2+,Cd2+可用0.5 mol/L硫脲+0.2 mol/L HNO3完全洗脱。其静态饱和吸附容量分别为16.63,24.86 mg/g。对2.0 mg/L的Cu2+,Cd2+的标准溶液液进行11次测定,相对标准偏差分别为3.3%和1.5%,检出限(3σ,n=11)分别为5.90,3.77μg/L。加标回收率分别95%~101%和99%~104%。方法可用于实际矿样中痕量铜、镉的测定。     

钛掺杂的非化学计量LiFePO4的合成与电化学性能研究

0 Introduction Phospho-olivine LiFePO4 as a prom ising cathode m aterialforlithium ion batteries has aroused consider- able interests due to its low cost, benign for environ- m ent, high tem perature capability and relatively high energy density[1,2]. Ith…     

槲皮素键合纳米硅胶对牛血清蛋白吸附的研究

具有生理活性的蛋白质、核酸、酶等生物大分子在维持现代人类健康方面已必不可少,在医疗和食品等领域已逐渐得到更广泛的应用,这也对蛋白质、核酸、酶等生物大分子的分离纯化、分析测定的提出了新的要求.     

以硅烷化硅胶为基质交联壳聚糖对重金属吸附的研究

本文通过对硅胶进行硅烷化,利用Shiff碱反应,用乙二醛作壳聚糖（CTS）交联剂和氨基化硅胶（Sigel-NH2）为偶联剂,制得结构稳定的2-（1,2-乙二醛）-亚胺-2-脱氧-β-D-葡聚糖树脂,并接枝于硅烷化TCL层析硅胶（简称为硅胶接枝2-乙二醛壳聚糖,Si-gel-g-BifCTS）.通过正交实验确定了合成Sigel-g-BifCTS的方法和最佳实验条件,并对CTS、Sigel-NH2和Sigel-g-BifCTS的结构和性能进行对比性的表征和分析.应用这种新的分离功能材料,研究了它对重金属离子Cd2＋、Pb2＋的吸附性能.     

硅胶-环糊精固定金属离子亲合吸附剂的制备及性能

以硅胶键合β-环糊精(-βCD)为载体,亚氨基二乙酸(IDA)为螯合基,制备了新型固定金属离子亲合吸附剂.通过13C固体核磁、元素分析对其进行了表征.每克吸附剂分别含IDA分子158μmol,-βCD分子136μmol.研究了吸附剂对α-淀粉酶的吸附特性.     

阴、阳离子表面活性剂混合体系在硅胶/水及硅胶/矿化水界面上的吸附

研究阴、阳离子表面活性剂混合体系(十二烷基氯代吡啶,辛基磺酸钠,辛基三乙基溴化铵/十二烷基苯磺酸钠)在硅胶,纯水和硅胶,矿化水界面上的吸附作用,探讨阴(阳)离子表面活性剂的存在对阳(阴)离子表面活性剂吸附作用的影响．结果表明,阴离子表面活性剂的存在基本不影响阳离子表面活性剂在带负电固体表面的吸附;而阳离子表面活性剂的存在却使本来吸附量就不大的阴离子表面活性剂在带负电的固体表面上不再吸附．在矿化水中阳离子表面活性剂的吸附量比在纯水中明显降低．从硅胶表面吸附机制解释了所得结果．     

Spectroscopic Study of Cerium-Doped Silica Gel Monoliths and Their Densified Derivatives

Cerium is exploited as a probe cation for elucidating the structure of an alkoxide-derived silica gel and its progressive evolution to a glass network as a function of heat-treatment up to 1000°C. At intermediate temperatures, the host structure exhibits inhomogeneity due to insufficient formation of siloxane bonds, which is reflected by at least two different sites and co-ordination spheres (termed “high” and “low” water ligation) for cerium. This is proved by the response of the gels heated up to 700°C to rehydration. Further formation of Si−O−Si network (900°C) leads to the destruction of the “high water” sites of cerium and progression towards a glassy structure. It is, however, only after heat-treatment at 1000°C that a dense silica glass network, not responding to rehydration, is finally obtained with cerium ions embedded in it.     

Adsorption from Ternary Liquid Mixtures on Partially Dehydroxylated Silica Gel

The formation of mixed adsorbed layers has been tested for ternary mixtures containing a specifically adsorbed component—acetone and binary solvent benzene +n-hepane. The specific excess adsorption isotherms from the liquid phase were measured on silica gel samples partially dehydroxylated. The competition of liquid components for silica surface is discussed on the basis of changes in the mixed solvent composition.     

Fabrication of Monolithic Silica in Microchannel as an Adsorbent for Preconcentration of VOCs

Abstract

Monolithic silica fabricated in microchannel by adding Methyltrimethoxysilane in starting composition of the sol used for preconcentration of volatile organic compounds was investigated in this study. Fabrication of monolithic silica in microchannel is difficult because of the shrinkage of monolithic silica. By adding Methyltrimethoxysilane in starting composition, the monolithic silica was successfully fabricated in a microchannel of a microchip. The developed microchip was used for preconcentration of VOCs followed by thermal desorption and GC/MS detection. It provides a good preconcentration method for developing an on-site VOCs monitoring micro total analysis system.     

Thermo-Kinetic Study of Piperazine Immobilized Silica Surface

In the present study, the degradation process of piperazine (PP) immobilized silica gel (SiPP) is investigated under dynamic conditions. The degradation of SiPP is studied with thermogravimetric analyzer (TGA). The kinetics of degradation process is analyzed by Kissinger method, Flynn–Wall–Ozawa's (FWO) method, and Deconvolution method. It is found that degradation of SiPP can be described by parallel independent two-portion process model, which includes two processing state of the system (marked by processes 1 and 2), where process 1 and 2 can be attributed to decomposition processes of organic moiety attached on silica surface. The apparent activation energy (E_a) is calculated by Flynn–Wall–Ozawa's (FWO) method and deconvolution method.     

卟啉试剂键合硅胶对蛋白质吸附行为的研究

报道了几种卟啉试剂键合硅胶的合成并研究了它们对蛋白质的吸附行为。结果表明 meso-四苯基卟啉键合硅胶 ( TPP· SG)对人血清白蛋白 ( HSA)的最大吸附容量为 1 3.4mg/g,最大吸附率达 92 % ,吸附平衡时间为 60 mi     

乙二胺硅胶复合材料对Zn2+的吸附特性

以γ-氯丙基三氯硅烷为偶联剂,将乙二胺偶合接枝在硅胶表面,合成对锌离子具有吸附作用的乙二胺硅胶复合材料（EDA/SiO2）,考察了Zn2+溶液pH值、初始浓度、吸附温度和吸附时间等因素对复合材料吸附性能的影响。 结果表明,在研究的溶液浓度及温度范围内,Zn2+溶液pH值对EDA/SiO2的吸附量影响显著,吸附的最佳pH值范围在3.0~5.5;Zn2+的吸附平衡数据符合Langmuir吸附模型,热力学数据显示,EDA/SiO2对Zn2+的吸附行为为一吸热且自发进行的过程,升高温度有利于吸附,并对此吸附行为作了解释;吸附动力学数据可用拟二级吸附动力学方程描述,得到的吸附速率常数与溶液初始浓度有关。     

Space-Selective Precipitation of Au Nanoparticles Inside Silica Gel

Au colloids were prepared by irradiation with a Nd:YAG laser. Au nanoparticles were characterized by absorption spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. It is found that the wavelength of the laser has no effect on the size but the number of the Au nanoparticles. By irradiating a transparent silica gel doped with gold ions with the focused laser in the gel and subsequent exposing in air, a space-selective pattern of letter “P” consisting of Au nanoparticles was observed inside the silica gel.