Preparation of nano-sized cerium and titanium pyrophosphates via solid-state reaction at room temperature

Nano-sized cerium-titanium pyrophosphates Ce1-xTixP2O7 （with x = 0, 0.2, 0.5, 0.7, 0.9, and 1.0） were obtained by grinding a mixture of Ce（SO4）2·4H2O, Ti（SO4）2, and Na4P2O7·10H2O in the presence of surfactant PEG-400 at room temperature, washing the mixture with water to remove soluble inorganic salts, and drying at 100℃. The products and their calcined samples were characterized using ultraviolet-visible spectroscopy （UV-vis）, thermogravimetry and differential thermal analyses （TG/DTA）, X-ray powder diffraction （XRD）, and transmission electron microscopy （TEM）. The results show that nano-sized Ce1-xTixP2O7 behave as an excellent UV-shielding material. Thereinto, the CeP2O7 has the most excellent UV-shielding effect, and the amorphous state of Ce0.8Ti0.2P2O7 can keep at a higher temperature than CeP2O7. Therefore, the stabilization of the amorphous state of the cerium pyrophosphates was carded out by doping titanium. This stabilization is a significant improvement, which enables to apply these amorphous pyrophosphates not only to cosmetics and paints, but also plastics and films.

SYNTHESIS OF THERMAL RESPONSE FACTORS AND Z-TRANSFER FUNCTION COEFFICIENTS FOR CALCULATION OF ROOM TEMPERATURE VARIATION

A new method is presented for getting the general thermal response factors and z-transfer functioncoefficients of a room by synthesizing them from the thermal response factors of different parts of the thermalinsulation structure. How to use the general thermal response factors and z-transfer function coefficients toca1culate the indoor air temperature variation directly is also studied. It is shown through practical use that it iseasy to program with the methods presented in this paper and the calculated results are reliable.

Ethanol-driven Room-temperature Synthesis of Potential Green-emitting Phosphors： a Case Study of Tb^3＋-doped CaHPO4

A novel green nanophosphor CaHPO4：Tb3＋ was synthesized via a room-temperatureco-precipitation route driven by ethanol solvent. X-ray powder diffraction （XRD）, scanningelectron microscopy （SEM） and photoluminescence spectroscopy （PL） techniques were utilizedto characterize the structure, morphology and fluorescence performance of the obtained powders.The results demonstrated that the prepared samples were well crystallized with triclinic phaseCaHPO4 structure and particle-like morphology. Photoluminescence measurements indicated thatCaHPOa：Tb3＋ had a strong absorption peak at 370 nm and exhibited characteristic emissions withseveral sharp peaks corresponding to the transitions 5D4-7FJ （jr = 6-3） of Tb3＋. Moreover, theluminescence optimum concentration for CaHPO4：Tb3＋ was determined to be 11 mol%, whichmight be a promising green-emitting ohosohor for display applications.

Room temperature synthesis of single-crystal Te nanorods from Na_2TeO_4

Single-crystalline tellurium nanorods were synthesized through the reduction of Na2TeO4 by hydrazine monohydrate, in the absence of surfactants, in an aqueous ammonia solution at room temperature. X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and selected area electron diffraction （SAED） were used to characterize the composition and morphology of the products. The concentration of the OH ion has a significant influence on the morphology of the products and is found to be responsible for tailoring the crystal growth dynamically： the concentration of Te blocking in the solution is reduced via increasing the concentration of the OH^- ion, and subsequently the nucleation rate of Te is suppressed and Te nanorods gradually grow because of the inherently anisotropic structure of Te. New generation tellurium atoms add to the surface of the particles during the long period of reaction.

Clean synthesis of calix[4]crown-5-sulfonyl cyclothiourea derivatives at room temperature in aqueous solution

Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cyclization of intramolecule at room temperature in aqueous solution. The advantages of the novel protocol are the mild reaction condition, free organic solvent, simple final treatment, easy isolation of products and excellent yields.

The Crystallization Behavior and Stability of Chromite Synthesized in Chromium-Containing Wastewater at Room Temperature

The ferrite process can not only purify wastewater containing heavy metal ions but also recycle valuable metals from wastewater. Therefore, it is considered a promising technology to treat chromiumcontaining wastewater. However, the process has not been extensively applied in industry due to its high synthesis temperature. In this paper, the feasibility of chromite synthesis at room temperature was comprehensively studied. The effects of critical factors on the effluent quality and the crystallization behavior and stability of the synthetic products were investigated. Results showed that the removal ratio of chromium from wastewater was over 99.0%, and the chromium concentration in the supernatant reached the sewage discharge standard after undergoing the ferrite process at room temperature. Increases in the aeration rate, stirring rate, and reaction time were favorable for the formation of stable chromite. The particles obtained by the ferrite process at room temperature were characterized by a compact structure, and the maximum size of the particles reached 52 μm. Chromium gradually entered the spinel crystal structure during the synthesis process, and the molecular formula of the synthetic chromite might be Fe3-xCrxO4, in which x was approximately 0.30. The path of the microscopic reaction was proposed to illuminate the synthesis mechanism of chromite under room temperature conditions. The present study has laid the foundation for the industrial application of the ferrite process in the purification and utilization of chromium-containing wastewater.

Modified room temperature solid-state synthesis of yttria-stabilized zirconia(YSZ) nano-powders for solid oxide fuel cells

High-performance solid oxide fuel cell(SOFC) is in urgent need of high-quality electrolyte powders with high reactivity and chemical uniformity.Here,8 mol% Y_(2)O_(3) doped ZrO_(2)(YSZ) nano-powders were synthesized by an improved solid-state reaction method at ambient temperature,and were applied to the fabrication of SOFC electrolytes.YSZ nano-powders show average grain sizes of ^(2)0 nm and high dispersibility,which is comparable with or even better than some other chemical methods.Benefitting from their high reactivity,dense YSZ electrolytes(relative density of 97.9%) can be obtained at a relatively low sintering temperature of 1400℃.The optimized electrical conductivity reaches up to a high value of0.034 S/cm at 800 0C in air.The anode supported single cell with the construction of Ni-YSZ/YSZ/Sm_(0.2)Ce_(0.8)O_(2-δ)(SDC)/La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF) exhibits the peak power density of 0.827 W/cm^(2) at800℃ while taking wet H_(2) as fuels and ambient air as oxidants.

Preparing Nano-ZnS by Solid State Reaction at Room Temperature

ZnS nanoparticles were prepared by using solid-state reaction method at room temperature in agate mortar for the first time. The average particle size was about 20nm. This reaction is affected by the structure of reactant, crystal water and defects.

Tuning composite solid-state electrolyte interface to improve the electrochemical performance of lithium-oxygen battery

Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durability as well as inferior electrochemical performance. Herein, in order to improve the safety and durability, a succinonitrile(SN) modified composite SSE is proposed. In this SSE, SN is introduced for eliminating the boundary between ceramic particles, increasing the amorphous region of polymer and ensuring fast ionic transport. Subsequently, the symmetric battery based on the proposed SSE achieves a long cycle life of 3000 h. Moreover, the elaborate cathode interface through the SN participation effectively reduces the barriers to the combination between lithium ions and electrons, facilitating the corresponding electrochemical reactions.As a result, the solid-state Li-O_(2)battery based on this SSE and tuned cathode interface achieves improved electrochemical performance including large specific capacity over 12,000 m Ah g^(-1), enhanced rate capacity as well as stable cycle life of 54 cycles at room temperature. This ingenious design provides a new orientation for the evolution of solid-state Li-O_(2)batteries.

Room-temperature synthesis of layered open framework cathode for sodium-ion batteries

The synthesis of active electrode materials at room temperature is one of the effective strategies to reduce the fabrication cost of sodium ion batteries(SIBs).Herein,a layered material(Na_(2)[(VO)_(2)(HPO_(4))_(2)C_(2)O_(4)]·2H_(2)O,abbreviated as NVPC followingly)with open-framework structures has been successfully prepared at room temperature under ambient conditions and is evaluated as a cathode for SIBs.It is revealed that NVPC cathode can deliver a maximum reversible capacity of ca.70 mAh/g at 10 mA/g,and exhibit superior rate capability and cycling performance:at 50 mA/g,maximum reversible capacity ca.50 m Ah/g with capacity retention of 88.4%over 250 cycles corresponds to only 0.046%capacity decay per cycle;at 100 mA/g,a maximum reversible capacity of 35 mAh/g with capacity retention of60.9%over 500 cycles.This study demonstrates a practical example of a low-cost synthesis of the cathode materials for SIBs.At the same time,the systematic electrochemical research results also show promising prospects for long lifespan low-cost SIBs.

A New Route for the Rapid Synthesis of Metal–Organic Frameworks at Room Temperature

Rapid synthesis of metal–organic frameworks(MOFs),especially high-valence MOFs at roomtemperature without external energy,is a challenging topic.In this work,a stable radical solution has been discovered.Various MOFs with versatile metal nodes and ligands were rapidly synthesized at room temperature in the absence of external energy.Especially,MOFs with conjugated ligands achieved instantaneous architecture(in less than 1 s)and quantitative yield.Radicals in the solution play a crucial role in the accelerated kinetics,and the new radical route paves a cyclic pathway for the MOF synthesis.The mechanism has been thoroughly investigated by electron paramagnetic resonance,in situ proton nuclear magnetic resonance,X-ray absorption spectra,in situ small-angle X-ray scattering-wide-angle X-ray scattering,and density functional theory calculations.

A New Dinuclear Zinc Polymer Based on 3-Methoxy-2-hydroxybenzaldehyde:Synthesis,Structure,Spectral Characterization and Hirshfeld Surface Analysis

A highly efficient fluorescence material dinuclear zinc polymer [Zn2（mhbd）2（dca）2]n （1, Hmhbd is 3-methoxy-2-hydroxybenzaldehyde, dca is N（CN）2？） has been synthesized under room temperature and structurally characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The structure belongs to the triclinic system, space group P with a = 8.475（1）, b = 9.595（1）, c = 15.001（1） A, α = 86.84（1）, β = 81.10（1）, γ = 68.78（1）°, Mr = 565.15, V = 1123.5（1） ？3, Dc = 1.671 g？cm–3, F（000） = 568, μ = 2.185 mm–1, R = 0.0451, and wR = 0.1297. 1 is a dinuclear zinc complex which further constructs a 1D chain through double μ1,5-dca bridge. Luminescent property and Hirshfeld surface analysis of 1 have been studied. The result indicates that the fluorescence intensity of complex 1 is forty-one times the fluorescence intensity of Hmhbd ligand.

碳六型聚羧酸减水剂的制备与性能研究

目的确定碳六型聚羧酸减水剂的最佳制备工艺,解决碳六型聚羧酸减水剂随存放时间延长保塑性下降的问题。方法以丙烯酸(AA)、乙二醇单乙烯基聚乙二醇醚(EPEG)及次亚磷酸钠(SHP)等为主要原材料,通过自由基共聚反应,制备得到了碳六型聚羧酸减水剂。通过水化热、SEM、XRD等测试方法,研究碳六型聚羧酸减水剂的性能。结果当聚醚单体分子量为3000、酸醚摩尔比为5∶1、起始反应温度为15~20℃时,碳六型聚羧酸减水剂的分散性及保塑性最佳。结论碳六型聚羧酸减水剂在分散性及保塑性方面均优于甲基烯丙基聚氧乙烯醚(HPEG)型减水剂;加入稳定剂后,碳六型聚羧酸减水剂的保塑性得到了明显提升。

2-Methylimidazole assisted ultrafast synthesis of carboxylate-based metal–organic framework nano-structures in aqueous medium at room temperature

Carboxylate-based metal–organic frameworks(CMOFs)have received considerable attentions for their high stability,catalytic activity,and porosity.However,synthesis of CMOFs requires high temperature,pressure,and long reaction time.Here,we explored the activity of 2-methylimidazole(2-MIM)for ultrafast synthesis of CMOF nanostructures(CMOFNs),in aqueous medium at room temperature and reaction time of 10 min.Seven CMOFNs have been synthesized by using Al3+,Cr3+,Cu2+,Fe3+,In3+,or Cd2+salt and1,4-bezenedicarboxylic acid,or 1,3,5-benzenetricarboxylic acid.Through this technique,the CMOFs with space time yield 181–501 kgcrystal sizes of ca.200–700 nm was obtained.

A review on room-temperature self-healing polyurethane:synthesis,self-healing mechanism and application

Polyurethanes have been widely used in many fields due to their remarkable features such as excellent mechanical strength, good abrasion resistance, toughness, low temperature flexibility, etc. In recent years, room-temperature self-healing polyurethanes have been attracting broad and growing interest because under mild conditions, room- temperature self-healing polyurethanes can repair damages, thereby extending their lifetimes and reducing maintenance costs. In this paper, the recent advances of room-temperature self-healing polyurethanes based on dynamic covalent bonds, noncovalent bonds and combined dual or triple dynamic bonds are reviewed, focusing on their synthesis methods and self-healing mechanisms, and their mechanical properties, healing efficiency and healing time are also described in detial. In addition, the latest applications of room-temperature self-healing polyurethanes in the fields of leather coatings, photoluminescence materials, flexible electronics and biomaterials are summarized. Finally, the current challenges and future development directions of the room-temprature self-healing polyurethanes are highlighted. Overall, this review is expected to provide a valuable reference for the prosperous development of room- temperature self-healing polyurethanes.

采用逆合成分析与纯有机催化室温合成4-溴查尔酮的实验设计

以4-溴查尔酮为目标分子,通过逆合成分析法,从6条路线中分析出含有5项诺贝尔奖成果的合成途径,通过对比,最后选择出2021年诺奖成果“纯有机催化”室温合成4-溴查尔酮。以新试剂L-脯氨酸为催化剂,室温下通过对溴苯甲醛和苯乙酮的羟醛缩合反应合成4-溴查尔酮,并进行一系列正交实验,优化反应条件。该反应具有原料价格低廉、反应条件温和等优点。通过简单的反应,将多项诺奖成果与纯有机催化引入实验教学中,避免“照方抓药”式教学,紧贴科学前沿,深化有机合成学习,有利于培养学生创新意识。

一锅法合成可印刷室温磷光二氟化硼衍生物

纯有机室温磷光(RTP)材料因其潜在的应用价值而备受关注.迄今,多数已报道的有机RTP材料在晶态下发射出较强的RTP,但在溶液加工过程中易生成无定形态,从而失去RTP性能.本文通过一锅法两步反应,合成了含有多个甲氧基的二氟化硼衍生物(BF2-tPMO).晶体结构分析表明,多个甲氧基的存在构建了有效的分子间非共价相互作用.这些非共价键作用可抑制分子运动,保持较高的发光效率.此外,这些非共价键作用能够使其在溶剂处理后依然保持晶态性质,进而保持RTP性能.实验结果表明,BF2-tPMO可溶解在不同溶剂中且在溶剂蒸发后仍能保持相同的RTP特性,为易加工型RTP材料的设计提供了有效的策略.

A new room temperature viscoelastic inorganic glass

Inorganic glass is a non-crystalline material that lacks of a regular,periodic atomic or molecular structure,and are considered as frozen liquids because of the similarity between their static amorphous structures.The atoms and molecules in the glass can gradually rearrange and realign with time,giving rise to deformation or aging in most glass materials.However,viscoelastic behavior could not be readily observable at room temperature(RT)due to its long time scale.The paper introduce and comment a recent work published in Nature Energy,which discover a new class of viscoelastic inorganic glass with Tg well below RT.The VIGLAS is simply synthesized through adding high content of oxygen into tetrachloroaluminates to replace chlorine.The VIGLAS exhibits characteristics similar to both inorganic ceramics and organic polymers,which are particularly relevant in the realm of battery electrolytes where a balance between ionic conductivity and chemo-mechanical compatibility is crucial.

EPEG缓释型聚羧酸减水剂的常温制备与性能研究

将乙二醇单乙烯基聚氧乙烯醚(EPEG)大单体与丙烯酸、丙烯酸羟乙酯通过自由基溶液共聚得到EPEG缓释型聚羧酸减水剂PCE-E,并分析了酸醚比、酯醚比、滴加时间等因素对PCE-E减水、缓释、保坍性能的影响。结果表明:当反应温度为20℃、酸醚比为2.10、酯醚比为2.9、引发剂用量为0.7%、还原剂用量为0.2%、催化剂用量为0.3%、链转移剂用量为0.4%、滴加时间为60 min时,制备得到的PCE-E综合性能最佳,在混凝土中的应用效果良好。