取代基对木质素三聚体模型化合物醚键均裂反应影响的密度泛函理论研究

利用密度泛函理论M062X/6-31++G(d,p)方法,对27种具有不同取代基(甲基、羟甲基和甲氧基)的木质素三聚体模型化合物的Cα-O和Cβ-O键均裂解离能进行了理论计算,探究了不同位置取代基对醚键解离能的影响规律。结果表明,当R2或R3位氢原子仅有一个被甲氧基取代时,Cβ-O键解离能变化很小;当R2、R3位氢原子均被甲氧基取代时,Cβ-O键解离能明显降低;且R4、R5位甲氧基能强化R2、R3位甲氧基对Cβ-O键解离能的降低程度,而不受R1位取代基的影响。当R4、R5位氢原子相继被甲氧基取代时,Cα-O键解离能逐渐降低,且R2、R3位甲氧基也能强化R4、R5位甲氧基对Cα-O键解离能的降低程度。当R1位氢原子相继被甲基、羟甲基取代时,Cα-O键解离能逐渐升高,然而R2、R3位甲氧基会弱化R1位甲基、羟甲基对Cα-O键解离能的升高程度;R1位甲基不会影响Cβ-O键解离能,羟甲基却能明显提高Cβ-O键解离能。     

Au单晶电极上H2O2的氧化反应研究

本文利用旋转圆盘电极系统研究了酸性介质中H₂O₂在Au(100)和Au(111)电极表面的电化学行为. 实验发现在Au电极上H₂O₂难以发生还原,但是当电位稍微正于H₂O₂氧化为O₂的平衡电势时即可发生氧化. 在Au(111)上H₂O₂氧化的起始电位比在Au(100)正0.1 V左右. Au(100)上的双桥位位点能增强反应中间体*OOH的吸附,可能是导致Au(100)上H₂O₂氧化反应超电势比Au(111)低的主要原因. 在较正电位区(E>1.2 V), 当电极表面被氧物种覆盖时,H₂O₂在两个电极上的氧化都会受到一定程度的抑制,这种影响在Au(111)上比Au(100)上更加明显,这与Au(111)上氧物种的生成与逆向还原可逆性差的趋势一致. 最后还将Au与Pt单晶电极上H₂O₂氧化的行为进行了对比分析.     

锂离子电池正极材料Li_(1.2)Mn_(0.54-x)Ni_(0.13)Co_(0.13)Zr_xO_2的制备及电化学性能

为了改善富锂锰基正极材料Li1.2Mn0.54Ni0.13Co0.13O2的循环性能,采用燃烧法合成了正极材料Li1.2Mn0.54-xNi0.13Co0.13ZrxO2(x=0.00,0.01,0.02,0.03,0.06).通过X射线衍射(XRD)和扫描电镜(SEM)对其结构与形貌进行了表征,利用恒电流充放电测试,循环伏安(CV)及电化学交流阻抗谱(EIS)技术对其电化学性能进行测试.结果表明,Li1.2Mn0.54-xNi0.13Co0.13ZrxO2(x=0.00,0.01,0.02,0.03,0.06)正极材料均具有α-NaFeO2型层状结构;在室温,2.0-4.8 V电压范围,以0.1C和1.0C(充放电电流以1.0C=180 mA·g-1计算)倍率充放电进行测试,样品Li1.2Mn0.52Ni0.13Co0.13Zr0.02O2的首次放电比容量分别为280.3和206.4 mAh·g-1.其中,在1.0C倍率下,100次循环后容量保持率由原来的73.2%提高到88.9%;以5.0C倍率充放电进行测试,经50次循环后,掺杂正极材料的放电比容量为76.5 mAh·g-1,而未掺杂材料仅有15.0 mAh·g-1.在50、25和-10°C,2.0C倍率条件下,掺杂正极材料的电化学性能均得到有效改善,其中,在-10°C经过50次循环后正极材料Li1.2Mn0.52Ni0.13Co0.13Zr0.02O2比未掺杂的正极材料相比,其放电比容量提高了61.1%.     

EXAFS/FT-IR characterization of tetra-iridium carbonyl clusters bound to tris-(hydroxymethyl)phosphine grafted silica surface catalytically active for propene oxidation to acetone

Structure and catalytic activity of Ir₄(CO)₁₂ bound to tris-(hydroxymethyl)phosphine (THP) grafted silica (THP/SiO₂) was investigated by means of EXAFS, FT-IR and kinetic studies. It was found that Ir₄(CO)₁₂ was uniformly attached on THP/SiO₂ by substitution of CO by THP (Ir₄/THP/SiO₂). The tetra-iridium carbonyl cluster framework was remained during the substitution of THP ligands and two THP ligands coordinated to the iridium carbonyl clusters to form Ir₄(CO)₁₀(THP/SiO₂)₂. species. When Ir₄/THP/SiO₂ was evacuated at 373 K, bridge CO was desorbed and Debye-Waller factor of Ir---Ir contribution derived from EXAFS analysis was increased which suggested that the cluster framework was distorted by the evacuation at 373 K. The resulting sample evacuated at 373 K was an active catalyst for hydroformylation of ethene and partial oxidation of propene, while the Ir₄/THP/SiO₂ without evacuation exhibited poor catalytic activities. The propene oxidation reaction proceed on the Ir₄/THP/SiO₂ evacuated at 323–353 K under subatmospheric pressures to give acetone as a product in high selectivity. The ethene hydroformylation proceed on the evacuated Ir₄/THP/SiO₂ at lower temperatures compared with other conventional iridium catalysts. EXAFS characterization and kinetic studies suggested that the catalytic activities were associated with the structural distortion of the iridium cluster framework due to surface attachment by the bidentate phosphine substitution.     

Preparation and characterization of sulfated zirconia (SO4/ZrO2)/Nafion composite membranes for PEMFC operation at high temperature/low humidity

Fine particle superacidic sulfated zirconia (SO₄²⁻/ZrO₂, S-ZrO₂) was synthesized by ameliorated method, and composite membranes with different S-ZrO₂ contents were prepared by a recasting procedure from a suspension of S-ZrO₂ powder and Nafion solution. The physico-chemical properties of the membranes were studied by ion exchange capacity (IEC) and liquid water uptake measurements, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, thermogravimetry–mass spectrometry (TG–MS) and Fourier transform infrared (FT-IR) spectroscopy. The results showed that the IEC of composite membrane increased with the content of S-ZrO₂, S-ZrO₂ was compatible with the Nafion matrix, the incorporation of the S-ZrO₂ could increase the crystallinity and also improve the initial degradation temperature of the composite membrane. The performance of single cell was the best when the S-ZrO₂ content was 15 wt.%, and achieved 1.35 W/cm² at 80 °C and 0.99 W/cm² at 120 °C based on H₂/O₂ and at a pressure of 2 atm, the performance of the single cell with optimized S-ZrO₂ was far more than that of the Nafion at the same condition (e.g. 1.28 W/cm² at 80 °C, 0.75 W/cm² at 120 °C). The 15 wt.% S-ZrO₂/Nafion composite membrane showed lower fuel cell internal resistance than Nafion membranes at high temperature and low relative humidity (RH).     

双二苯基-1-甲基咪唑膦氯化镍的制备及其电催化还原CO2的研究

以二苯基-1-甲基咪唑膦（dpim）为配体制备了一种新型的配合物催化剂Ni(dpim)₂Cl₂. 循环伏安研究表明,Ni(dpim)₂Cl₂配合物在氮气气氛下表现出两步还原的电化学行为,在-0.7 V下为两电子的不可逆还原,在-1.3 V下为单电子准可逆还原. 向电解液中通入CO₂后,在-1.3 V下的还原峰变得不可逆,且其峰电流从0.48 mA·cm^-2增大到0.55 mA·cm^-2. 在质子源（CH₃OH）存在的条件下,该还原峰电流可继续增大到0.72 mA·cm^-2. 该研究结果表明,Ni(dpim)₂Cl₂配合物对CO₂还原具有良好的电催化性能,且其电催化还原过程符合ECE机理. 在-1.3 V下恒电位电解得到的还原产物主要为CO,催化转换频率（Turnover of Frenquency, TOF）为0.17 s^-1.     

Emission quenching of binuclear pyrophosphito platinum(II) complexes in aqueous solution by sulphur dioxide. Spectroscopic measurements on sulphur dioxide addition and chromous ion reduction

The emission intensity at 517 nm from Pt₂(pop)₄⁴⁻ (pop = P₂O₅H₂²⁻) is quenched by the addition of sulphur dioxide. The sulphur dioxide coordinates at the axial platinum(II) sites by a η¹-SO₂ bond. This coordination is supported by ³¹p NMR and Raman spectroscopy of aqueous solutions. The electronic spectrum of a sulphur dioxide saturated solution of Pt₂(pop)₄⁴⁻ shows an absorption at 428.5nm ( = 4.1 × 10⁴). From the decrease in the chromophore for uncomplexed Pt₂(pop)₄⁴⁻ the equilibrium constant for SO₂ binding is estimated to be 1.74 M₂l⁻². The effect of adding different quenchers to aqueous solutions of Pt_2(pop)4⁴⁻ is discussed. The compound Pt₂(pop)₄⁴⁻ will undergo 2-electron reduction with chromous ion.     

Synthesis, characterization and thermal investigation of M[M(C2O4)3]·xH2O (x=4 for M=Cr(III); x=2 for M=Sb(III) and x=9 for M=La(III))

The complexes, M[M(C₂O₄)₃]·xH₂ O, where x=4 for M=Cr(III), x=2 for M=Sb(III) and x=9 for M=La(III) have been synthesized and their thermal stability was investigated. The complexes were characterized by elemental analysis, IR and electronic spectral data, conductivity measurement and powder X-ray diffraction (XRD) studies. The chromium(III)tris(oxalato)chromate(III)tetrahydrate (COT), Cr[Cr(C₂ O₄)₃]·4H₂O, released water in a stepwise fashion. Removal of the last trace of water was accompanied by a partial decomposition of the oxalate group. Thermal investigation using TG, DTG and DTA techniques in air produced Cr₂O₃ at 858°C through the intermediate formation of Cr₂O₃ and CrC₂O₄ at around 460°C. While DSC study in nitrogen up to 670°C produced a mixture of Cr₂O₃ and CrC₂O₄. In antimony(III)tris(oxalato)antimonate(III)dihydrate (AOD), Sb[Sb(C₂O₄)₃]·3H₂O the dehydration took place during the decomposition of precursor at 170–290°C and finally at ca. 610°C Sb₂ O₅ along with trace amounts of Sb₂O₄ were produced. Trace amount of Sb₂O₃ and Sb along with Sb₂O is proposed as the end product at 670°C of AOD in nitrogen. The oxide La₂O₃ is formed at 838°C from the study with TG, DTG and DTA in air of lanthanum(III)tris(oxalato)lanthanum(III)nonahydrate (LON), La[La(C₂O₄)₃]·9H₂O. Intermediate dioxycarbonate, La₂O₂CO₃ was generated at 526°C prior to its decomposition to lanthanum oxide in air; whereas in N₂ the formation of La₂(CO₃)₃ at 651°C was proposed. The thermal parameters have been evaluated for each step of the dehydration and decomposition of COT, AOD and LON using five non-mechanistic equations i.e. Flynn and Wall, Freeman and Carroll, Modified Freeman and Carroll, Coats–Redfern and MacCallum–Tanner equations. Kinetic parameters, such as, E^*, k_o, ΔH^*, ΔS^* etc. were also supplemented by DSC studies in nitrogen for all the three complexes. Some of the intermediate species have been identified by analytical and powder XRD studies. Tentative schemes has been proposed for the decomposition of all three compounds in air and nitrogen.     

三元掺杂改性锂离子电池正极材料Li3V2(PO4)3

以柠檬酸为螯合剂和还原剂, NH₄VO₃为钒源,通过溶胶-凝胶法制备了锂离子电池正极材料Li₃V₂(PO₄)₃及其三元掺杂体系Li_2.85Na_0.15V_1.9Al_0.1(PO₄)_2.9F_0.1.分别采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、能量损失谱(EELS)、拉曼(Raman)光谱、扫描电子显微镜(SEM)、X射线能谱(EDS)、恒流充放电、循环伏安(CV)和交流阻抗谱(EIS)等技术对材料的微观结构、颗粒形貌和电化学性能进行分析.结果表明:在残余碳包覆的基础上, Na、Al、F三元掺杂有利于稳定Li₃V₂(PO₄)₃的晶体结构,进一步减少颗粒团聚和提升材料导电特性,促进第三个锂离子的脱出和嵌入,从而显著改善Li₃V₂(PO₄)₃的实用电化学性能.未经掺杂的Li₃V₂(PO₄)₃原粉在1/9C、1C和6C倍率下的可逆比容量分别为141、119和98 mAh·g^-1,而三元掺杂改性材料在1/9C、1C、8C和14C倍率下的比容量分别为172、139、119和115 mAh·g^-1.在1C倍率下循环300圈后,掺杂体系的比容量依然高达118 mAh·g^-1,比原粉高出32.6%.值得注意的是,这种三元掺杂还使Li₃V₂(PO₄)₃的多平台放电曲线近似转变为一条斜线,显示出可能不同的储锂机制.     

锂离子电池高镍正极材料掺铝的作用及掺铝方法的研究

为了探究铝对高镍层状氧化物在结构、形貌及性能方面的影响,本文采用两种不同的方式掺铝以制备NCA正极材料 （LiNi_0.8Co_0.15Al_0.05O₂）：一是固相法即将共沉淀合成的NC前驱体（Ni_0.84Co_0.16(OH)₂）在混锂烧结过程混入铝源（纳米Al₂O₃或Al(NO₃)₃）;二是共沉淀法即直接在合成前驱体过程中混入铝源（Al₂(SO₄)₃或NaAlO₂）即合成NCA前驱体（Ni_0.8Co_0.15Al_0.05(OH)_2.05）后再混锂烧结. 结果表明,掺铝能够降低阳离子混排程度、维持层状结构的稳定性,改善材料在充放电循环过程的放电电压及中值电压大幅下降的情况,提高其循环性能. 其中以NaAlO₂为铝源合成NCA前驱体所制备的NCA材料性能最优：在3.0 ~ 4.3 V充放电区间,0.1C倍率下首圈放电比容量达198 mAh·g^-1,首次库仑效率可达94.6%,1C倍率下循环200圈后容量保持率达70%.     

计时电量法求NiCl2(bpy)3在DMF中的扩散系数和速率常数

讨论了NiCl₂(bpy)₃(bpy：2,2-联吡啶)在DMF中的电化学行为. 控制电位使电极过程处于扩散控制下, 采用计时电量法求得了29 ℃时NiCl₂(bpy)₃在DMF中的扩散系数为5.99×10^－6 cm²•s^-1, 不同温度下的扩散系数随温度升高而增大. 选择合适的电极电位, 使电极过程处于扩散和电化学混合控制下, 采用计时电量法求得了不同电极电位下的反应速率常数k_f, 以及不同温度下的标准速率常数k⁰, 求得了表观活化能为14.4 kJ•mol^-1.     

低温甲烷氧化偶联纳米SrTi_(0.975)Li_(0.025)O_(3-δ)催化剂的原位ESR和TPSR表征

采用溶胶-凝胶法制备纳米钙钛矿型复合氧化物催化剂SrTi1-xLixO3-δ(x=0、0.025、0.050),用微型催化反应评价装置结合XRD、TEM、原位ESR和程序升温表面反应(TPSR)等方法,研究甲烷氧化偶联(OCM)纳米SrTi1-xLixO3-δ催化剂结构和催化性能。结果表明,B位掺杂适量的低价Li+离子可优化纳米SrTiO3催化剂低温(~650℃)甲烷氧化偶联催化性能,Li+掺杂量为0.025时获得最高的甲烷转化率和C2选择性。与柠檬酸法制相同组成的常规催化剂相比,SrTi0.975Li0.025O3-δ纳米催化剂具有较优良的低温OCM催化性能和相同温度下更高的C2选择性。SrTi0.975Li0.025O3-δ纳米催化剂优良的催化性能与其表面原子配位不饱和存在F中心相关。     

The reactions of a dinuclear ferric complex (oxo) di-iron(III) triethylenetetraamminehexaacetate, Fe2O(ttha), with oxidizing and reducing free radicals. A pulse radiolysis study

The rate constants at which oxidizing and reducing radicals react with the dinuclear iron(III) complex Fe₂O(ttha)²⁻ were measured in neutral aqueous solution. The rate constants for reduction of the complex by ·CO₂^.− CH₃^.CHOH and O₂^.− were found to be comparable with rate constants previously measured in mononuclear iron(III) polyaminocarboxylate systems. Fe₂O(ttha)²⁻ reacts slowly with O₂^.− (k₈ = (1.2 ± 0.2) × 10⁴ dm³ mol⁻¹ s⁻¹) and, hence, is a relatively poor catalyst for the dismutation of superoxide radical. The hydrated electron reduces the complex at a diffusion-controlled rate in a process which consumes one proton: e_aq⁻ + Fe₂O(ttha)²⁻ → Fe₂^III,IIO(ttha)³⁻ The reduction by carbon-centered radicals produces a (III,II) mixed-valence complex with an absorption spectrum different from that of the Fe₂(II,III) species produced from reduction by the hydrated electron. The oxidizing radicals ^.OH and ·CO₃⁻ appear to act as reductants of the complex via ligand oxidation rather than by oxidation of the Fe₂^IIIO core to Fe₂^III,IVO. In the former case ligand attack appears to occur mainly at the methylene carbon of a glycinate group. The decarboxylation product, CO₂, was detected by its aquation reaction in the presence of a pH sensitive dye, bromthymol blue.     

草酸二甲酯气相催化加氢合成乙二醇的研究

采用共沉淀法制备了一系列 CuO/SiO₂ 催化剂,进行草酸二甲酯气相加氢活性评价,分别考察了不同沉淀剂（Na₂CO₃、NH₃·H₂O、NaOH）、催化剂组成以及反应工艺条件对加氢性能的影响。采用N₂ 吸附脱附、N₂O吸附、XRD、TG热重分析、H₂-TPR等手段对催化剂进行表征。结果表明,草酸二甲酯加氢反应活性与Cu⁰有关,提高铜比表面积有利于提高加氢活性。采用以NaOH沉淀剂制备的CuO质量分数为50%的CuO/SiO₂催化剂,在200℃、2MPa、0.07h^-1和氢酯摩尔比为100时,草酸二甲酯转化率可达 98%,乙二醇选择性87%,且催化剂表现出较好的稳定性。     

合成高产率的Au21(SR)15纳米簇

近年来,精确原子个数的金纳米簇因其在催化、生物医药、传感等领域具有潜在应用而备受关注。本研究中使用金刚烷硫醇(HS-Adam)作为配体制备了Au₂₃(S-Adam)₁₆纳米簇。在室温条件下,通过HS-Adam刻蚀Au₂₃(S-Adam)₁₆纳米簇,得到了纯度较高的Au₂₁(S-Adam)₁₅,其转换率可达20% (根据金原子计算)。并通过紫外可见吸收光谱(UV-Vis),电喷雾(ESI)和基质辅助激光解析飞行时间(MALDI)质谱以及热重分析(TGA)对合成的金纳米簇进行表征。     

Nd3+-doped Li3V2(PO4)3 cathode material with high rate capability for Li-ion batteries

A series of Nd3+-doped Li3NdxV2àx(PO4)3(x = 0.00, 0.02, 0.05, 0.08 or 0.1) composites are synthesized by the rheological phase reaction method. The XRD results indicate that Nd3+ions have been successfully merged into a lattice structure. Doped samples show good electrochemical performance in high discharge rate and long cycle. In the potential range of 3.0–4.3 V, Li3Nd0.08V1.92(PO4)3exhibits an initial discharge capacity of 115.8 m Ah/g at 0.2 C and retain 80.86% of capacity retention at 2 C in the 51 st cycle.In addition, Li3Nd0.05V1.95(PO4)3holds at 100.4 m Ah/g after 80 cycles at 0.2 C with a capacity retention of92.4%. Finally, the CV test proves that the potential polarization of Li3Nd0.08V1.92(PO4)3decreased compared with the un-doped one.     

Hydrogen peroxide photoproduction by the semicarbazide—tris(2,2′-bipyridine)ruthenium(II)—oxygen system

A light-driven system consisting of tris(2,2′-bipyridine)ruthenium(II) (Ru(bpy)₃²⁺) as the photosensitizer, semicarbazide as the electron donor and molecular oxygen as the electron acceptor has been employed for hydrogen peroxide production. The efficiency of this photosystem markedly depends on pH: while the peroxide yield is almost negligible at acid, neutral or slightly alkaline pH, it reaches significant values at high hydroxide concentrations, the initial rate of H₂O₂ formation drastically increasing from pH 12 to pH 14. In 1 M NaOH solutions containing Ru(bpy)₃²⁺ and semicarbazide at optimum concentrations, the number of catalytic cycles (or turnover number) undergone by the ruthenium complex over the complete course of the photochemical reaction is as high as 1.1 × 10⁴.

Spectrofluorometric and laser flash photolysis techniques were used to study the primary photochemical reactions involving the excited state of the ruthenium complex as well as the photochemically generated species Ru(bpy)₃³⁺ and Ru(bpy)₃⁺. It is proposed that at pH 14 a sequence of reactions leading to O₂ photoreduction by electrons from semicarbazide takes place, with the concomitant formation of H₂O₂; the excited state of Ru(bpy)₃²⁺ appears to react via oxidative quenching by oxygen rather than via reductive quenching by semicarbazide. At neutral pH, in contrast, there is no H₂O₂ formation owing to the fact that semicarbazide is unable to reduce (Ru(bpy)₃³⁺ to Ru(bpy)₃²⁺, although the photoexcited ruthenium complex is quenched equally by oxygen.     

还原温度对低温还原法制备的Ni_2P/Ti-MCM-41催化剂加氢脱硫性能的影响

以氯化镍(Ni Cl_2·6H_2O)为镍源、次磷酸铵(NH_4H_2PO_2)为磷源、Ti-MCM-41为载体,通过程序升温还原法制备了Ni_2P/Ti-M CM-41催化剂,并采用H_2-TPR、XRD、BET、XPS、TEM等手段对其结构和性质进行了表征。以二苯并噻吩(DBT)为模型化合物,考察了还原温度对Ni_2P/Ti-M CM-41催化剂的加氢脱硫(HDS)性能的影响。结果表明,程序升温还原法制备的Ni_2P/Ti-M CM-41催化剂前驱体的还原温度为318℃,比传统程序升温还原制备的Ni_2P低200℃。在350-500℃下还原得到的催化剂活性相为单一的Ni_2P相,较低的还原温度有利于形成更小粒径的磷化镍晶粒。还原温度为400℃时,制得的Ni_2P/Ti-M CM-41催化剂比表面积高、分散性最好、表面P富集少,具有最高的HDS活性;在340℃、3.0 M Pa、H_2/油体积比500、质量空速(WHSV)为2.0 h~(-1)的条件下,二苯并噻吩HDS转化率达到99.4%。     

Fraction of excited-state oxygen formed as b Σg in solution-phase-photosensitized reactions II. Effects of sensitizer substituent

The fraction F_Σ of excited-state oxygen formed as b ¹Σ_g⁺ was determined for a series of triplet-state photosensitizers in CCl₄ solutions. F_Σ was determined by monitoring the intensities of (a) O₂(b ¹Σ_g⁺) fluorescence at 1926 nm (O₂(b ¹Σ_g⁺)→O₂(a ¹Δ_g) and (b) O₂(a ¹ Δ_g) phosphorescence at 1270 nm (O₂(a ¹Δ_g) → O₂(X³Σ_g⁻)). Oxygen excited states were formed by energy transfer from substituted benzophenones and acetophenones. The data indicate that F_Σ depends on several variables including the orbital configuration of the lowest triplet state and the triplet-state energy. The available data indicate that the sensitizer-oxygen charge transfer (CT) state is not likely to influence F_Σ strongly by CT-mediated mixing of various sensitizer-oxygen states.     

Syntheses, crystal structures and characterizations of new zinc (II) and lead (II) carboxylate-phosphonates

The syntheses, crystal structures and characterizations of two new divalent metal carboxylate-phosphonates, namely, Zn(H₃L)·2H₂O (1) and Pb(H₃L)(H₂O)₂ (2) (H₅L4-HO₂C–C₆H₄–CH₂N(CH₂PO₃H₂)₂₎ have been reported. Compound 1 features a 1D column structure in which the Zn(II) ions are tetrahedrally coordinated by four phosphonate oxygen atoms from four phosphonate ligands, and neighboring such 1D building blocks are further interconnected via hydrogen bonds into a 3D network. The carboxylate group of H₃L anion remains non-coordinated. Compound 2 has a 2D layer structure. Pb(II) ion is 7-coordinated by four phosphonate oxygen atoms from four phosphonate ligands and three aqua ligands. The interconnection of Pb(II) ions via bridging H₃L anions results in a 001 layer. The carboxylate group of the H₃L anion also remains non-coordinated and is oriented toward the interlayer space. Solid state luminescent spectrum of compound 1 exhibits a strong broad blue fluorescent emission band at 455 nm under excitation at 365 nm at room temperature.