Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
Chemphyschem. 2012 Jun 4;13(8):2162-9. doi: 10.1002/cphc.201101009. Epub 2012 Apr 16.
A unique direct electrodeposition technique involving very high current densities, high voltages and high electrolyte concentrations is applied for highly selective mass synthesis of stable, isolable, surfactant-free, single-crystalline Bi hexagons on a Cu wire at room temperature. A formation mechanism of the hexagons is proposed. The morphology, phase purity, and crystallinity of the material are well characterized by FESEM, AFM, TEM, SAED, EDX, XRD, and Raman spectroscopy. The thermal stability of the material under intense electron beam and intense laser light irradiation is studied. The chemical stability of elemental Bi in nitric acid shows different dissolution rates for different morphologies. This effect enables a second way for the selective fabrication of Bi hexagons. Bi hexagons can be oxidized exclusively to α-Bi(2)O(3) hexagons. The Bi hexagons are found to be promising for thermoelectric applications. They are also catalytically active, inducing the reduction of 4-nitrophenol to 4-aminophenol. This electrodeposition methodology has also been demonstrated to be applicable for synthesis of bismuth-based bimetallic hybrid composites for advanced applications.
一种独特的直流电沉积技术，涉及非常高的电流密度、高电压和高电解质浓度，用于在室温下在铜丝上高度选择性地大规模合成稳定、可分离、无表面活性剂的单晶 Bi 六边形。提出了六边形的形成机制。通过 FESEM、AFM、TEM、SAED、EDX、XRD 和拉曼光谱对材料的形貌、相纯度和结晶度进行了很好的表征。研究了材料在强电子束和强激光照射下的热稳定性。研究了元素 Bi 在硝酸中的化学稳定性，不同形态的溶解速率不同。这种效应为 Bi 六边形的选择性制造提供了第二种方法。Bi 六边形可以被氧化为纯的 α-Bi(2)O(3)六边形。发现 Bi 六边形在热电应用中很有前景。它们还具有催化活性，能将 4-硝基苯酚还原为 4-氨基酚。该电沉积方法还被证明可用于合成用于高级应用的基于铋的双金属混合复合材料。
