Low temperature synthesis of BiFeO$_{3}$ nanoparticles with enhanced magnetization and promising photocatalytic performance in dye degradation and hydrogen evolution
In this investigation, we have synthesized BiFeO$_{3}$ nanoparticles by varying hydrothermal reaction temperatures from 200 $^{\circ}$C to 120 $^{\circ}$C to assess their visible-light-driven photocatalytic activity along with their applicability for hydrogen production via water splitting. The rhombohedral perovskite structure of BiFeO$_{3}$ is formed for hydrothermal reaction temperature up to 160 $^{\circ}$C, however, for a further decrement of reaction temperature a mixed sillenite phase is observed. The XRD Rietveld analysis, XPS analysis and FESEM imaging ensure the formation of single-phase and well crystalline nanoparticles at 160 $^{\circ}$C reaction temperature with 20 nm of average size. The nanoparticles fabricated at this particular reaction temperature also exhibit improved magnetization, reduced leakage current density and excellent ferroelectric behavior. These nanoparticles demonstrate considerably high absorbance in the visible range with a low bandgap (2.1 eV). The experimentally observed bandgap is in excellent agreement with the calculated bandgap using the first-principles calculations. The favorable photocatalytic performance of these nanoparticles has been able to generate more than two times of solar hydrogen compared to that produced by bulk BiFeO$_{3}$ as well as commercially available Degussa P25 titania. Notably, the experimentally observed bandgap is almost equal for both bulk material and nanoparticles prepared at different reaction temperatures. Therefore, in solar energy applications, the superiority of BFO nanoparticles prepared at 160 $^{\circ}$C reaction temperature may be attributed not only to solely their bandgap but also to other factors, such as reduced particle size, excellent morphology, well crystallinity, large surface to volume ratio, ferroelectricity and so on.
Impact of reaction temperatures on the particle size of V2O5 synthesized by facile hydrothermal technique and their auspicious photocatalytic performance in dye degradation
在本研究中，采用绿色温和水热法，在100 °C ~ 200 °C的六个不同温度下，以20 °C为步长，全面研究了水热反应温度对V2 O 5合成及物性的影响。. XRD图谱证实了在所有反应温度下合成的样品具有稳定的正交晶体结构。SEM和TEM图像显示了颗粒状形貌，这些表征证实了颗粒尺寸随着反应温度的升高而变大。采用FTIR分析了产物的官能团，所得结果与XRD分析结果一致。已经使用UV-vis漫反射光谱（UV-DRS）在各种反应温度下估计了带隙，并且发现带隙在2.09 eV至2.15 eV之间变化，这是吸收显著量的可见光的合适范围。以亚甲蓝（MB）为目标染料，研究了合成样品的光催化降解性能.在较低的反应温度（100 °C）下合成的纯V2 O 5具有较低的带隙，因此具有较高的光催化效率。
Photocatalytic Degradation of Methylene Blue by ZnO/NiFe2O4 Nanoparticles
本文报道了在高温（850 °C）下通过煅烧ZnO纳米棒和NiFe 2 O 4棱柱纳米棒10小时成功地固相合成ZnO/NiFe 2 O 4纳米复合材料。这些纳米材料的结构，功能基团和形态的研究，分别采用XRD，FTIR和SEM。以亚甲基蓝（MB）染料的光催化降解为例，考察了催化剂的光催化活性.光催化研究表明，ZnO/NiFe 2 O 4纳米复合材料在紫外光下具有较高的降解效率。研究表明，ZnO/NiFe 2 O 4纳米粒子去除亚甲基蓝溶液中，OH和光生空穴h+是主要物种。采用固相法将NiFe_2 O_4与绿色合成的ZnO偶联制备ZnO/NiFe_2 O_4纳米复合材料是本文的创新之处。合成的ZnO/NiFe 2 O 4纳米复合材料在生活和工业废水处理方面具有潜在的应用前景。
Sustainable and green synthesis of hydrogen tungsten bronze nanoparticles with nanocarbon via mechanically induced hydrogen spillover
在这项研究中，我们展示了可持续的和绿色的纳米技术，室温下合成H $_x$ WO $_3$（$0<x<0.5$）通过一种新的反应途径诱导的机械能。使用单斜WO $_3$粉末和聚烯烃（聚丙烯）的简单混合物来获得H $_x$ WO $_3$纳米颗粒，其即使通过高能球磨合成也显示出高结晶度。H $_x$ WO $_3$纳米粒子和纳米碳副产物的复合物在可见光下表现出独特的光电性能以及对偶氮染料水污染物的光催化降解性能的显著增强。并对所得功能材料的形成机理进行了探讨。本研究的发现提供了对H $_x$ WO $_3$纳米颗粒的大规模生产的限制的见解，例如用于电化学反应和贵金属催化的特定设置。
Magnetoelectrically driven catalytic degradation of organics
在这里，我们报告的催化降解有机化合物，利用磁电（ME）性质的钴铁氧体-铋铁氧体（CFO-BFO）核壳纳米粒子。磁致伸缩CFO与多铁性BFO的组合产生了磁电发动机，其在无线磁场下经由高级氧化过程净化水，而不涉及任何牺牲分子或助催化剂。磁致伸缩CoFe 2 O 4纳米粒子的制备使用水热合成，然后通过溶胶-凝胶合成，以创建多铁性BiFeO 3壳。通过理论模拟研究了磁电纳米颗粒表面的磁场诱导极化。从这些模拟得到的结果是一致的实验结果的压电力显微镜分析，在那里我们观察到的纳米粒子的压电响应的变化下磁场。接下来，我们研究了交流磁场下磁电效应诱导的催化降解有机污染物，并获得了97%的合成染料的去除率和85%以上的常规药物的去除率。此外，我们进行捕获实验，以阐明背后的机制磁场诱导的催化降解有机污染物通过使用清除剂的每一个反应物种。结果表明，羟基和超氧自由基是磁电诱导催化降解有机物的主要活性物种。
Interfacial Synergy in Ag-Doped CuO-AgCl-g-C3N4 Composites for Efficient Charge Separation and Low-power Methylene Blue Degradation
Indian Institute of Technology Indore（印度印多尔理工学院）；Heriot-Watt University（赫瑞-瓦特大学）；Ariel University（阿里埃勒大学）；King Fahd University of Petroleum and Minerals（法赫德国王石油与矿物大学）
