粉煤灰基NaA/NaX双晶型沸石分子筛构建及其协同吸附氨氮性能

以粉煤灰为原料,采用“联合改性三步合成法”——超声辅助碱熔微波晶化法联合废旧玻璃/13X晶种/NaH₂PO₄浸渍三阶段改性合成沸石分子筛(GFS);作为对比,采用传统碱熔水热法合成沸石分子筛(FS);采用“三步合成法”——超声辅助碱熔微波晶化法合成沸石分子筛(WFS)。并采用X射线衍射(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)、能量色散光谱(EDS)、N₂吸附-脱附等方法对材料的组成、形貌和结构进行了表征。结果表明,WFS和GFS较FS具有更高的比表面积和发达的介孔、微孔,且沸石分子筛晶型从NaA单晶型转为NaA/NaX双晶型。氨氮吸附实验结果表明,GFS (56.01 mg·g^-1)较WFS (49.17 mg·g^-1)和FS (39.75 mg·g^-1)吸附性能更优,吸附动力学和热力学数据符合二级动力学模型和Langmuir模型,氨氮吸附过程为以离子交换为主的吸附,且为自发放热过程,低温促进氨氮吸附。     

PO43-掺杂和AlF3包覆协同增强Li1.2Ni0.13Co0.13Mn0.54O2正极材料电化学性能

本研究采用PO₄^3-掺杂和AlF₃包覆的协同改性策略制备了P-LNCM@AlF₃正极材料(P=PO₄^3- ,LNCM=Li_1.2Ni_0.13Co_0.13Mn_0.54O₂),提高了LNCM的结构稳定性以及抑制了界面副反应。其中,大四面体的PO₄^3-聚阴离子掺杂在晶格中抑制了过渡金属离子的迁移,降低体积变化,从而稳定了晶体结构,而且PO₄^3-掺杂能够扩大锂层间距,促进Li⁺的扩散,从而提升材料的倍率性能。此外,AlF₃包覆层能抑制材料与电解液的副反应从而提升界面稳定性。基于以上优势,P-LNCM@AlF₃正极表现出了优异的电化学性能。在1C电流密度下表现出了179.2 mAh·g^-1的放电比容量,循环200圈后仍有161.5 mAh·g^-1的放电比容量,容量保持率可达90.12%。即使在5C的高电流密度下仍可提供128.8 mAh·g^-1的放电比容量。     

Li3V2(PO4)3的溶胶-凝胶合成及其性能研究

以LiOH·H₂O(LiF、Li₂CO₃、LiCH₃COO·2H₂O)、NH₄VO₃、H₃PO₄和柠檬酸为原料,采用Sol-gel法合成锂离子电池正极材料Li₃V₂(PO₄)₃。优化了锂源、溶胶的pH值、预烧条件、煅烧温度等合成条件,并采用XRD、SEM、恒电流充放电及循环伏安试验等方法,研究了所合成的Li₃V₂(PO₄)₃的结构形貌和电化学性能。结果表明,以LiOH·H₂O为锂源,溶胶的pH值等于3,于氩气氢气(体积比9∶1)混合气中300 ℃预烧 4 h,并在氩气氢气(体积比9∶1)混合气中600 ℃煅烧8 h合成的Li₃V₂(PO₄)₃正极材料为标准的单斜结构,具有较高的放电比容量和较好的循环稳定性,0.1C和1C倍率下首次放电比容量分别为130 mAh·g^-1和129 mAh·g^-1;1C倍率下循环40次后,容量仍为127 mAh·g^-1,容量保持率为98.4%;随后又进行10C倍率放电,10次循环后容量为105 mAh·g^-1,容量保有率达98.1%。循环伏安测试表明,该正极材料具有较好的电化学可逆性。     

聚乙烯亚胺改性氧化石墨对水中Cr(Ⅵ)的吸附

通过对石墨氧化、酯化,将聚乙烯亚胺耦合接枝到氧化石墨表面,制备聚乙烯亚胺改性氧化石墨(PEI-GO)。通过FTIR、XRD、TEM、RS和XPS等对合成材料进行表征,并研究了其对水中的Cr(Ⅵ)吸附和脱附性能。表征结果表明,聚乙烯亚胺成功嫁接到氧化石墨上,其氨基含量为4.36mmol·g^-1。PEI-GO对水中Cr(Ⅵ)具有很好的吸附性能,吸附等温线符合Freundlich方程,吸附动力学可用拟二级动力学方程来描述。PEI-GO对水中Cr(Ⅵ)的吸附随pH的升高而降低。阴离子的存在降低吸附剂对Cr(Ⅵ)的吸附,不同阴离子的影响大小顺序为PO₄^3- >SO₄^2- >NO₃^- >Cl^-。XPS结果表明,PEI-GO对Cr(Ⅵ)的去除是吸附-化学还原耦合作用的结果。经4次脱附再生循环,PEI-GO对Cr(VI)仍具有较高吸附量,表明该吸附剂再生性好,可循环使用。     

聚乙烯亚胺改性氧化石墨对水中Cr(Ⅵ)的吸附

通过对石墨氧化、酯化,将聚乙烯亚胺耦合接枝到氧化石墨表面,制备聚乙烯亚胺改性氧化石墨(PEI-GO).通过FTIR、XRD、TEM、RS和XPS等对合成材料进行表征,并研究了其对水中的Cr(Ⅵ)吸附和脱附性能.表征结果表明,聚乙烯亚胺成功嫁接到氧化石墨上,其氨基含量为4.36 mmol·g^-1.PEI-GO对水中Cr(Ⅵ)具有很好的吸附性能,吸附等温线符合Freundlich方程,吸附动力学可用拟二级动力学方程来描述.PEI-GO对水中Cr(Ⅵ)的吸附随pH的升高而降低.阴离子的存在降低吸附剂对Cr(Ⅵ)的吸附,不同阴离子的影响大小顺序为PO₄^3- >SO₄^2- >NO^3- >Cl^-.XPS结果表明,PEI-GO对Cr(Ⅵ)的去除是吸附-化学还原耦合作用的结果.经4次脱附再生循环,PEI-GO对Cr(VI)仍具有较高吸附量,表明该吸附剂再生性好,可循环使用.     

低温固相反应合成Li3V2(PO4)3正极材料及其性能

利用V₂O₅·nH₂O湿凝胶，LiOH·H₂O，NH₄H₂PO₄和C等作原料，通过低温固相还原反应在550 ℃焙烧12 h制备出Li₃V₂(PO₄)₃正极材料。采用XRD，SEM和电化学测试对Li₃V₂(PO₄)₃样品性能进行研究。XRD研究表明本法所合成的Li₃V₂(PO₄)₃同传统的高温固相反应法所合成的Li₃V₂(PO₄)₃一样同属于单斜晶系结构。SEM测试表明所合成的样品平均粒径大小约为0.5 μm且粒径分布较窄。电化学测试表明以0.2 C的倍率放电时，样品的首次放电容量为130 mAh·g^-1，室温下循环30次后其比容量为124 mAh·g^-1。     

MoO42-取代对Nasicon型Li3Fe2(PO4)3正极材料电化学性能的影响

以MoO₄^2-部分取代Li₃Fe₂（PO₄）₃中的PO₄^3-,研究表明：加入的MoO₄^2-离子主要以固溶形式存在于Li₃Fe₂（PO₄）₃中,起到了显著改善其电化学性能的作用。其中,MoO₄^2-掺杂浓度为0.3的样品表现出最佳的电化学性能,其在0.5C倍率下的首次放电容量为113.7 mAh·g^-1,这一数值比未掺杂的提高了20.7%;经过60次循环充放电,容量保持率为94%。将放电倍率从0.5C逐步增大至5C,再降至初始的0.5C,并在每个倍率循环10次,这一材料的最终放电容量可达首次0.5C的95%。这些优异的性能应归因于MoO₄^2-掺杂使材料的氧化还原能力增强,氧化还原电对的电势差减小,电池内部的电荷转移电阻减小,以及Li⁺扩散系数增加。     

Li3V2(PO4)3的溶胶-凝胶法合成及其性能研究

以LiOH·H₂O、NH₄VO₃、H₃PO₄和柠檬酸等为原料采用溶胶-凝胶法合成了锂离子二次电池正极材料磷酸钒锂(Li₃V₂(PO₄)₃)。考察了煅烧温度和配位剂种类等条件对产物组成及电化学性能的影响。研究了优化条件下制得样品的循环伏安、充放电性能和循环性能。0.1 C条件下,样品首次放电比容量达129.81 mAh·g^-1，经过100次循环后容量几乎没有衰减，仍保持在128 mAh·g^-1。X射线衍射研究表明合成单一Li₃V₂(PO₄)₃晶体所需温度比固相法低；并考察了循环20次后材料充电到各个单相的晶体结构，通过X射线衍射和最小二乘法计算给出了其晶胞参数变化过程，证实了循环嵌Li过程中晶体结构能够得到重现。     

维铜基配位聚合物的合成、结构和离子对其吸附Cr(Ⅵ)的影响

配位聚合物通常具有较大的比表面积和结构容易调控的特点,能有效地吸附去除水中的Cr(Ⅵ)。以4,4''-联吡啶（bipy）、1,3-间苯二乙腈（1,3-dab）、Cu （ClO₄）₂·6H₂O为原料,通过水热合成的方法成功合成了二维铜基配位聚合物：{[Cu （bipy）₄（1,3-dab）][Cu （bipy）₂（ClO₄）₂]（ClO₄）₂·（1,3-dab）}_n （1）。利用红外、X射线单晶衍射、元素分析、X射线光电子能谱等表征方法对1的结构进行测试分析。结果表明,1属于正交晶系P222₁空间群,a=1.115 52（5） nm,b=1.116 66（4） nm,c=3.116 84（15） nm,V=3.882 5（3） nm³。吸附Cr(Ⅵ)的性能研究表明,吸附剂1的最佳投料浓度为0.04 g·L^-1;在pH=3~9的范围内均具有较好的吸附性能和pH适应性,并且在pH=5时吸附性能最好,吸附容量能达到250 mg·g^-1。离子共存实验表明离子浓度越大、价态越高,它们对1吸附Cr(Ⅵ)的影响就越明显,并且阴离子的抑制作用高于金属阳离子,作用大小顺序： PO₄^3->SO₄^2->CO₃^2->Cl^->HCO₃^->NO₃^-。     

以还原型钼磷酸盐[P4MoV6O28(OH)3]9-为建筑单元构筑新型多维延展结构材料

向MoO₃, H₃PO₄和bpy(4,4′-bipyridine)组成的反应体系中分别引入Cd(OAc)₂·2H₂O 和MnCl₂·4H₂O, 在水热条件下合成了两种基于还原型钼磷酸盐[P₄Mo₆O₂₈(OH)₃]^9-(简称{P₄Mo₆})为建筑单元构筑的新型多维延展型无机-有机杂化材料(H₂bpy)₂[Cd(H₂O)]₃[Cd(HPO₄)₆(PO₄)₂(OH)₆(MoO₂)₁₂]·5H₂O(1)和 (H₂bpy)₃[Mn(H₂O)₂]₂ [Mn(HPO₄)₆(PO₄)₂(OH)₆(MoO₂)₁₂]·10H₂O(2), 并通过元素分析、红外光谱、热重分析和X射线单晶衍射对其进行了表征。结果表明, 化合物1和2均属于三斜晶系, P1 空间群。化合物1的阴离子[Cd(H₂O)]₃[Cd(HPO₄)₆(PO₄)₂(OH)₆(MoO₂)₁₂]^2-是由二聚体 Cd[P₄Mo₆]₂通过{Cd₃}簇依次连接形成的一维无机链状结构; 化合物2的阴离子[Mn(H₂O)₂]₂[Mn(HPO₄)₆(PO₄)₂(OH)₆(MoO₂)₁₂]^3-则是由二聚体Mn[P₄Mo₆]₂通过Mn²⁺离子连接形成的二维无机层状结构。这2种无机延展结构均同质子化的bpy通过氢键作用形成不同的三维超分子网络。同时还探讨了化合物2的电化学性质。     

Removal of uranium(VI) from aqueous solutions by new phosphorus-containing carbon spheres synthesized via one-step hydrothermal carbonization of glucose in the presence of phosphoric acid

The novel phosphorus-rich hydrothermal carbon spheres (HCSs–PO₄) have been synthesized via one-step hydrothermal carbonization of glucose in the presence of phosphoric acid. The textural and surface chemistry properties were characterized using Boehm titrations, scanning electron microscopy and Fourier transform infrared spectrometer. The content of oxygen-containing functional groups on the surface of HCSs increased from 0.053 to 1.009 mmol g^?1 by phosphate group modification. The adsorption ability of HCSs–PO₄ has been explored for the removal of uranium from aqueous solutions. The adsorption kinetic data were best described by the pseudo-second-order equation. Adsorption process could be well defined by the Langmuir isotherm, the adsorption capacity of HCSs increased from 80.00 to 285.70 mg g^?1 after phosphate group modification. And thermodynamic parameters indicated the adsorption process was feasible,endothermic and spontaneous. Selective adsorption studies showed that the HCSs–PO₄ could selectively remove U(VI), and the selectivity coefficients had been improved in the presence of co-existing ions, Na(I), Ni(II), Sr(II), Mn(II), Mg(II) and Zn(II). Complete removal (99.9 %) of U(VI) from 1.0 L industry wastewater containing 15.0 mg U(VI) ions was possible with 12.0 g HCSs–PO₄.     

Study on the mechanism of removing fluoride from wastewater by oxalic acid modified aluminum ash-carbon slag-carbon black doped composite

In this study, SAA@CS-CB(aluminum-ash carbide slag carbon black doped composite) was prepared by sintering method and modified by impregnation with oxalic acid to obtain SAA@CS-CB_oa. Fluoride adsorption experiments were carried out using this composite as adsorbent. With increasing pH values, the adsorption amount of fluoride decreases in the range of 2–11. The pseudo second order equation and Langmuir model were fit to the experimental data, and the adsorption of fluoride by SAA@CS-CB_oa exhibited spontaneous and endothermic characteristics. When PO₄^3-, CO₃^2–, SO₄^2-, Cl^-, NO₃^–, Br^- and HCO₃^– anions were individually or combined in solution, the adsorbents exhibited higher fluoride selectivity and sensitivity, while PO₄^3-and CO₃^2– weakened the adsorption of fluoride in solution in the same way regardless of the presence of the other 5 anions. The results of SEM, EDS, XRD and FTIR characterizations showed that the mechanism of fluoride adsorption and removal by SAA@CS-CB_oa included the combined effects of electrostatic attraction, surface coordination precipitation and ion exchange. SAA@CS-CB_oa is an effective composite material for water adsorption of fluoride, and still has an excellent performance of cyclic regeneration after 10 times adsorption desorption. This study provides a new approach for the utilization of fluoride removal resources for industrial solid waste resource recycling.     

A dihydrogen phosphate anionic network as a host lattice for cations in 1‐methylpiperazine‐1,4‐diium bis(dihydrogen phosphate) and 2‐(pyridin‐2‐yl)pyridinium dihydrogen phosphate–orthophosphoric acid (1/1)

In the salt 1‐methylpiperazine‐1,4‐diium bis(dihydrogen phosphate), C₅H₁₃N₂²⁺·2H₂PO₄⁻, (I), and the solvated salt 2‐(pyridin‐2‐yl)pyridinium dihydrogen phosphate–orthophosphoric acid (1/1), C₁₀H₉N₂⁺·H₂PO₄⁻·H₃PO₄, (II), the formation of O—H...O and N—H...O hydrogen bonds between the dihydrogen phosphate (H₂PO₄⁻) anions and the cations constructs a three‐ and two‐dimensional anionic–cationic network, respectively. In (I), the self‐assembly of H₂PO₄⁻ anions forms a two‐dimensional pseudo‐honeycomb‐like supramolecular architecture along the (010) plane. 1‐Methylpiperazine‐1,4‐diium cations are trapped between the (010) anionic layers through three N—H...O hydrogen bonds. In solvated salt (II), the self‐assembly of H₂PO₄⁻ anions forms a two‐dimensional supramolecular architecture with open channels projecting along the [001] direction. The 2‐(pyridin‐2‐yl)pyridinium cations are trapped between the open channels by N—H...O and C—H...O hydrogen bonds. From a study of previously reported structures, dihydrogen phosphate anions show a supramolecular flexibility depending on the nature of the cations. The dihydrogen phosphate anion may be suitable for the design of the host lattice for host–guest supramolecular systems.     

钙镁磷肥(FCMP)阴离子构型的硅烷化气相色谱(TMS-GC)研究

通过对钙镁磷肥(FCMP)硅烷化气相色谱(TMS-GC)的研究证明:FCMP中硅以一聚、二聚、三聚链及环四构型为主,同时还有少量其他一维、二维、三维构型存在;而磷则以单个四面体与硅聚合或独立存在。     

Surface and internal modification of composite ion exchange membranes for removal of molybdate,phosphate, and nitrate from polluted groundwater

Al₂O₃/chitosan-multiwall carbon nanotubes (MWCNTs) were created to increase the exchange capacity of polyvinylidene fluoride (PVDF) ion-exchange membranes. The composite membranes were made by mixing Al₂O₃ nanoparticles into the PVDF cast solution, then applying a thin coating of chitosan functionalized carbon nano tubes (Cs-MWCNTs) to the PVDF membrane surface. The structure and characteristics of the hybrid membranes were described using XRD, SEM, IR, and TG-DTA. The Al₂O₃-PVDF/Cs-MWCNTs membrane beat the other Al₂O₃-PVDF/Cs, Al₂O₃-PVDF, and PVDF membranes in terms of molybdate, phosphate, and nitrate adsorption. The removal efficiency, pH solution, adsorption capacity, and desorption process of molybdate, phosphate, and nitrate anions by Al₂O₃-PVDF and PVDF membranes were investigated. The removal effectiveness of molybdate, phosphate, and nitrate, according to the testing findings, was 94.3, 65.6, and 85.78 %, respectively. The adsorption of MoO₄^2?, PO₄^3?, and NO₃^? increased as the pH increased initially until the best adsorption was achieved, and then decreased significantly as the pH increased further. The total adsorption capabilities of MoO₄^2?, PO₄^3?, and NO₃^?for the Al₂O₃-PVDF/Cs-MWCNTs membrane were 65.50, 61.22, and 59.77 mg/g, respectively. Using regeneration and reuse experiments for the simultaneous adsorption of molybdate, phosphate, and nitrate during three consecutive cycles, the adsorption/desorption of Al₂O₃-PVDF/Cs-MWCNTs was assessed. Al₂O₃-PVDF/Cs-MWCNTs offer a lot of promise when it comes to eliminating MoO₄^2?, PO₄^3?, and NO₃^?from actual wastewater samples.     

粉煤灰磁性吸附剂的制备及磷吸附机理

通过化学沉淀法制备了CMS@La_2O_3磁性磷吸附剂。结构及磁性表征显示,氧化镧较均匀的包覆在粉煤灰磁珠表面;样品的比磁化强度达20.35 emu·g~(-1),可实现高效磁分离。利用钼酸铵分光光度法对所得磁性吸附剂的磷吸附性能进行了试验研究。研究表明,其最高磷比饱和吸附量可达19.50 mg·g~(-1),吸附时间、pH值、共存阴离子等因素对磷吸附效果均具有显著影响。吸附动力学拟合表明,CMS@La_2O_3对含磷离子的吸附符合准二级动力学方程,以化学吸附为主,磁性吸附剂对含磷离子的吸附反应过程可由La_2O_3表面羟基化-离子交换模型解释。吸附磷后的CMS@La_2O_3吸附剂经处理后可多次循环使用。     

Ion-exchange properties of microdispersed sintered detonation nanodiamond

The adsorption of transition metal cations and inorganic anions from aqueous solutions on microdispersed sintered detonation nanodiamond (MSDN) is systematically studied. The selectivity series Fe³⁺ > Al³⁺ > Cu²⁺ > Mn²⁺ > Zn²⁺ > Cd²⁺ > Co²⁺ > Ni²⁺ with maximum adsorption capacity between 2 and 5 µmol g^?1 is obtained. It is found that anions may significantly contribute to the adsorption of transition metal cations, so the adsorption of CH₃COO^?, Cl^?, B₄O₇ ^2?, ClO₄ ^?, I^?, SO₄ ^2?, C₂O₄ ^2?, PO₄ ^3? is also studied. For the first time, dominating adsorption of anions over cations is demonstrated for detonation nanodiamond. The maximum anion-exchange capacity of 50–150 µmol g^?1 is found for MSDN. Beside of electrostatic interactions, the formation of complexes with hydroxyl groups and interaction with metal impurities contribute to the adsorption of B₄O₇ ^2? and PO₄ ^3?, respectively. Therefore, anion exchange selectivity of MSDN is different from that observed for common anion exchange resins. In all cases, the adsorption on MSDN obeys Langmuir law. The pH effect on the adsorption of SO₄ ^2?, PO₄ ^3? and B₄O₇ ^2? is different from that observed for other anions due to specific interactions.     

Fast recovery of Au (III) and Ag(I) via amine-modified zeolitic imidazolate framework-8

In this paper, zeolitic imidazolate framework-8 modified by the ethanediamine (NH₂-ZIF-8) was employed for adsorbing Au (III) and Ag(I) from aqueous solutions. The adsorption capacities of NH₂-ZIF-8 towards Au (III) and Ag(I) were found to be significantly affected by the pH values of the solution. The adsorption kinetics studies show that NH₂-ZIF-8 presents a fast adsorption property towards metals, attaining 93% of adsorption equilibrium uptake for Au (III) within the first 30 min. This phenomenon can be ascribed to the coordination interaction between the amino group and Au (III). The thermodynamic data suggest that the adsorption of NH₂-ZIF-8 towards Au (III) is endothermic process, while that for Ag(I) is exothermic. The maximum adsorption capacities of NH₂-ZIF-8 toward Au (III) and Ag(I) can be achieved to 357 mg·g⁻¹ and 222.25 mg·g⁻¹, respectively. The metal ions interference results show that Cu (II) and Ni (II) hardly have no interference on Au (III) adsorption in e-waste containing 1500 mg·l⁻¹ Cu (II),100 mg·l⁻¹ Ni (II) and 10 mg·l⁻¹ Au (III); while for Ag(I), Cd (II) and Zn (II) have little interference on Ag(I) adsorption in the hybrid solutions containing Ag(I), Ni (II), Cd (II) and Zn (II) with equal concentration (50 mg·l⁻¹), but Ni (II) interference most. The XPS study shows that partial Au (III) was reduced to Au(I), and that Ag(I) was completely reduced to Ag(0) during the adsorption process. The abundant of active sites of NH₂-ZIF-8 containing C=N, N-H, and Zn-OH groups play a key role in the adsorption of Au (III) and Ag(I). In addition, electrostatic interaction can be responsible for the adsorption of Au (III) by NH₂-ZIF-8. The regeneration experiments results show that the adsorption capacities of NH₂-ZIF-8 towards Au (III) and Ag(I) can maintain after three cycles. This work provides a reliable method to improve the adsorption kinetics for metal ions.     

Evaluation of phosphate removal capacity of Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>–ZVINPs from aqueous solution: optimization using response surface analysis

The present research aims to optimize the removal of phosphate (PO₄ ^3?) from aqueous solution by Fe₃O₄ stabilized zero-valent iron nanoparticles (Fe₃O₄–ZVINPs). A three-factor, three-level, Box–Behnken design combined with response surface methodology was applied to design the experiments, to develop a mathematical model, and for evaluating the individual and also the interactive effects of the operating variables like pH, temperature, and PO₄ ^3? concentration on removal efficiency. The analysis of variance has been used to evaluate the adequacy of the developed mathematical model in order to predict the optimal conditions of independent process variables, and to get maximum removal efficiency. Three-dimensional response surface plots were constructed to visualize the simultaneous interactive effects between two process variables. All three factors had a significant impact on removal of PO₄ ^3?. The predicted value of the model (166.0 mg g^?1PO₄ ^3?) was in good agreement with the experimental value (164.92 mg g^?1 PO₄ ^3?) under the optimum conditions of temperature 49.2 °C; pH 3.5; and PO₄ ^3? concentration 79.8 mg L^?1. The removal of PO₄ ^3? in the presence of environmental matrix (other ions) was also investigated at optimum conditions as predicted by the model. The results suggest that the presence of these ions had no significant effect on PO₄ ^3? removal. In addition, the adsorbed PO₄ ^3? can be effectively desorbed at higher pH of the solution. The findings suggest that removal of PO₄ ^3? from aqueous solution using Fe₃O₄–ZVINPs can be an effective method.     

1,15-Diferrocenyl-2,5,8,11,14-pentaazapentadecane,an Open-Chain Redox-Active Ferrocene-Functionalized Polyazaalkane Ligand for Anions

The interaction of the ferrocene-functionalized open-chain polyazaalkane 1,15-diferrocenyl-2,5,8,11,14-pentaazapentadecane (L¹) with the sulfate, phosphate, and ATP anions has been studied by potentiometric methods in THF/H₂O 70 : 30 (v/v) (containing 0.1M (Bu₄N)ClO₄ at 25°). Additionally, the electrochemical response of L¹ in the presence of H⁺, HSO^-₄, H₂PO^-₄, Br⁻, and Cl⁻ in a non-aqueous solvent such as MeCN has been studied. A remarkable cathodic shift of the ferrocene oxidation potential was induced for phosphate (198 mV) and sulfate (145 mV) showing an EC mechanistic response. Competitive electrochemical studies showed that L¹ is able to electrochemically and selectively recognize HSO^-₄ vs. H₂PO^-₄ in a mixture of both anions in MeCN.