Publication date: 15th December 2014
Efficiently splitting water using photoelectrochemical (PEC) cell into H2 could become a key technology towards clean, sustainable fuels. Si has suitable Eg and band alignments for the photocathode of tandem water splitting device. And also, efficient H2 production (HER) with open circuit voltage over 0.5 V and photocurrent over 20 mA cm-2 has been shown experimentally using pn+-Si homojunction with Pt co-catalyst. However, as current performance of Si PEC cells far behinds its theoretical limit, the need for different approach increases. Above all, carrier-selective contacts design with efficient carrier transport and low recombination using metal-oxide-semiconductor (MOS) structure comes into the spotlight recently. The key feature is chemical surface passivation by tunneling oxide interlayer and selective carrier transport due to an energy barrier for majority carrier by highly doped layer. This provides favorable structure for high photovoltage, however, very little work has been done studying H2 production using PEC cell with MOS structure. Talin’s group demonstrated HER using Pt/Ti/SiO2/p-Si with Voc of 490 mV, but it has inevitable limitation in current density due to the light absorption by metallic layers. Moreover, there has been no detail report on energy band level analysis to understand how the carriers can be selectively injected. In present work we demonstrate Pt/TiO2/poly-Si:P/SiO2/p-Si (front) and p-Si/SiO2/poly-Si:B/Al (back) to both front and back contacts which provide interface passivation and selective injection of minority and majority carrier to solid/liquid interface and back contact, respectively. The samples with carrier-selective contacts showed almost 100 mV enhanced photovoltage compared with reference Si electrode with conventional pn-junction. Using poly-Si as a metallic layer of MOS structure has been employed in recent state-of-art MOS based photovoltaic cells, but combination with TiO2 for PEC hydrogen has not been shown so far. Moreover, the details working principles based on the band energy analysis are outlined to understand how the carriers can be injected selectively and transferred to solid/liquid interface in PEC system.
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.