Wadhwa Ritika, Yadav Krishna K, Goswami Tanmay, Guchhait Sujit Kumar, Nishanthi S T, Ghosh Hirendra N, Jha Menaka
Institute of Nano Science & Technology, Knowledge City, Sector-81, Mohali, Punjab-140306, India.
Electrochemical Power Sources Division, CSIR-CECRI, Karaikudi 630006, Tamil Nadu, India.
ACS Appl Mater Interfaces. 2021 Mar 3;13(8):9942-9954. doi: 10.1021/acsami.0c21010. Epub 2021 Feb 19.
Surface decoration of metal oxides by metals for enhancing their electrocatalytic properties for organic conversions has attracted a lot of researchers' interest due to their high abundancy, inexpensiveness, and high stability. In the present work, a process for the synthesis of black gold (BG) using a citrate assisted chemical route and m-ZrO by a hydrothermal method at 200 °C has been developed. Further, different concentrations of black gold are being used to decorate the surface of zirconia by exploitation of surface potential of zirconia and gold surfaces. The catalyst having 6 mol % concentration of black gold shows excellent electrocatalytic activity for ethanol oxidation with low oxidation peak potential (1.17 V) and high peak current density (8.54 mA cm). The current density ratio (j/j) is also high (2.54) for this catalyst indicating its high tolerance toward poisoning by intermediate species generated during the catalytic cycle. The enhanced electrocatalytic activity can be attributed to the high tolerance of gold toward CO poisoning and high stability of the ZrO support. The black gold decorated zirconia catalyst showed enhanced activity during photoelectrochemical studies when the entire spectrum of light falls on the catalyst. Ultrafast transient studies demonstrated plasmonic excitation of metallic free electrons and subsequent charge separation in the black gold-ZrO heterointerface as the key factor for enhanced photoelectrocatalytic activity.
通过金属对金属氧化物进行表面修饰以增强其用于有机转化的电催化性能，因其高丰度、低成本和高稳定性而吸引了众多研究人员的关注。在本工作中，已开发出一种使用柠檬酸盐辅助化学路线合成黑金（BG）以及在200℃通过水热法合成m-ZrO的方法。此外，利用氧化锆和金表面的表面电势，使用不同浓度的黑金来修饰氧化锆表面。具有6 mol％黑金浓度的催化剂对乙醇氧化表现出优异的电催化活性，具有低氧化峰电位（1.17 V）和高的峰电流密度（8.54 mA cm）。该催化剂的电流密度比（j/j）也很高（2.54），表明其对催化循环过程中产生的中间物种中毒具有高耐受性。增强的电催化活性可归因于金对CO中毒的高耐受性以及ZrO载体的高稳定性。当整个光谱照射到催化剂上时，黑金修饰的氧化锆催化剂在光电化学研究中表现出增强的活性。超快瞬态研究表明，金属自由电子的等离子体激元激发以及黑金-ZrO异质界面中随后的电荷分离是增强光电催化活性的关键因素。
