Electron emission from H-terminated diamond enhanced by polypyrrole grafting. (May 2021)

• Record Type: Journal Article
• Authors: Ukraintsev, Egor; Kromka, Alexander; Janssen, Wiebke; Haenen, Ken; Takeuchi, Daisuke; Bábor, Petr; Rezek, Bohuslav
• Is Part Of: Carbon. Volume 176(2021)
• Page Start: 642
• Page End: 649
• Publication Date: 2021-05
• Subjects: Diamond -- Surfaces -- Electron emission -- Electron affinity -- Polypyrrole -- Kelvin probe; AFM atomic force microscope -- BDD boron doped diamond -- KPFM Kelvin probe force microscopy -- NEA negative electron affinity -- PEA positive electron affinity -- PPy polypyrrole -- SE secondary electron SEM scanning electron microscope -- SIMS secondary ion mass spectroscopy -- TPYS total photoelectron yield spectroscopy -- XPS x-ray induced photoelectron spectroscopy -- UPS ultraviolet light induced photoelectron spectroscopy; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2020.12.043
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: Electron emission plays an important role in diverse applications, from cold cathodes to chemical processes (solvated electrons, water purification), energy generation (thermionic or dye-sensitized solar cells), and even cancer treatment. Here we show that by surface treatment using electrochemically grown polypyrrole the secondary-electron emission and photoelectron emission from boron-doped diamond is enhanced even above the intensity of electron emission from the hydrogen-terminated surface with negative electron affinity. This enhancement is stable in air for at least one month and it persists also in vacuum after thermal annealing. Scanning electron microscopy, Kelvin probe force microscopy, total photoelectron yield spectroscopy as well as surface mapping by Auger and secondary ion mass spectroscopies are used to characterize and correlate the surface electronic and chemical properties. A model of the electron emission enhancement is provided. Graphical abstract: Image 1 Highlights: Molecular scale modification enhances electron emission from diamond. Enhanced electron emission is stable in air and after thermal annealing in vacuum. Enhancement observed for secondary electrons in electron microscope. Enhancement observed in photoelectron emission.