Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Hydrogen sensors based on electrophoretically deposited Pd nanoparticles onto InP | Grym et al. Nanoscale Research Letters 2011 6 392 http content 6 1 392 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Hydrogen sensors based on electrophoretically deposited Pd nanoparticles onto InP Jan Grym1 Olga Prochazkova1 Roman Yatskiv1 and Katerina Piksová2 Abstract Electrophoretic deposition of palladium nanoparticles prepared by the reverse micelle technique onto InP substrates is addressed. We demonstrate that the substrate pre-deposition treatment and the deposition conditions can extensively influence the morphology of the deposited palladium nanoparticle films. Schottky diodes based on these films show notably high values of the barrier height and of the rectification ratio giving evidence of a small degree of the Fermi level pinning. Moreover electrical characteristics of these diodes are exceptionally sensitive to the exposure to gas mixtures with small hydrogen content. Introduction Metal nanoparticles MNPs form a bridge between bulk materials and atomic or molecular structures. Bulk metals show constant size-independent physical properties while the properties of MNPs are driven by their size shape and inter-particle distance. Surface properties are crucial because the number of surface atoms becomes significant as the MNP reaches the nanoscale limit 1 . III-V semiconductors have established their position in electronic devices thanks to their unique properties. As compared to silicon they offer higher operating speeds lower power consumption or higher light emission efficiency. However to fully exploit their properties there is one key point remaining to be solved. III-V semiconductor structures suffer from a high density of surface interface states causing so called Fermi level pinning FLP 2 . The mechanism responsible for the FLP at the metal-semiconductor interface has been a subject of a long-term discussion. We consider the disorder-induced gap state model stating that large energy .
