Scientists grow 'nanonets' able to snare added energy transfer

September 03, 2008

Using two abundant and relatively inexpensive elements, Boston College chemists have produced nanonets, a flexible webbing of nano-scale wires that multiplies surface area critical to improving the performance of the wires in electronics and energy applications.

Researchers grew wires from titanium and silicon into a two-dimensional network of branches that resemble flat, rectangular netting, Assistant Professor of Chemistry Professor Dunwei Wang and his team report in the international edition of the German Chemical Society journal Angewandte Chemie.

By creating nanonets, the team conquered a longstanding engineering challenge in nanotechnology: creating a material that is extremely thin yet maintains its complexity, a structural design large or long enough to efficiently transfer an electrical charge.

"We wanted to create a nano structure unlike any other with a relatively large surface area," said Wang. "The goal was to increase surface area and maintain the structural integrity of the material without sacrificing surface area and thereby improving performance."

Tests showed an improved performance in the material's ability to conduct electricity through high quality connections of the nanonet, which suggest the material could lend itself to applications from electronics to energy-harvesting, Wang said. Titanium disilicide (TiSi2) has been proven to absorb light across a wide range of the solar spectrum, is easily obtained, and is inexpensive. Metal silicides are also found in microelectronics devices.

The nanonets grew spontaneously from the bottom-up through simple chemical reactions, unprovoked by a catalyst, according to Wang and co-authors, post doctoral researcher Xiaohua Liu and graduate students Sa Zhou and Yongjing Lin.

Basic nano structures are commonly created in zero or one dimension, such as a dot composed of a small number of atoms. The most complex structures grow in three dimensions - somewhat resembling the branches of a tree. Working in 2D, Wang's team produced a web that under a microscope resembles a tree with all branches growing in the same perpendicular direction from the trunk.

Using titanium disilicide intrigued Wang because of the material's superior conductivity. Late last year, researchers at the Max Planck Institute for Bioinorganic Chemistry observed that a titanium disilicide semiconductor photo catalyst splits water into hydrogen and oxygen. The semiconductor also stores the gases produced, enabling the simple separation of hydrogen and oxygen. So-called water splitting may play a key role in producing hydrogen for fuel.

"We're excited to have discovered this unique structure and we are already at work to gauge just how much the nanonet can improve the performance of a material that is already used in electronics and clean energy applications," said Wang.

Boston College

---

---

	Energy Transfers (Energy Essentials: Freestyle Express) by Nigel Saunders (Author), Steven Chapman (Author) This book tells you about the amazing world of energy. It explains what the different types of energy are and how they can change. The facts are linked to the real world and how different forms of energy help us live our lives. Energy is everywhere!
	Energy Makes Things Happen (Let's-Read-and-Find-Out Science 2) by Kimberly Brubaker Bradley (Author), Paul Meisel (Illustrator) Did you know that energy comes from the food you eat? From the sun and wind? From fuel and heat? You get energy every time you eat. You transfer energy to other things every time you play baseball. In this book, you can find out all the ways you and everyone on earth need energy to make things happen.
	Capture Dynamics and Chaotic Motions in Celestial Mechanics: With Applications to the Construction of Low Energy Transfers by Edward Belbruno (Author) This book describes a revolutionary new approach to determining low energy routes for spacecraft and comets by exploiting regions in space where motion is very sensitive (or chaotic). It also represents an ideal introductory text to celestial mechanics, dynamical systems, and dynamical astronomy. Bringing together wide-ranging research by others with his own original work, much of it new or previously unpublished, Edward Belbruno argues that regions supporting chaotic motions, termed weak stability boundaries, can be estimated. Although controversial until quite recently, this method was in fact first applied in 1991, when Belbruno used a new route developed from this theory to get a stray Japanese satellite back on course to the moon. This application provided a major verification of his...
	Energy Transfer Equities, L.P. by SGA Lists (Author)
	Energy Transfer Partners L.P. by SGA Lists (Author)
	Energy Medicine in Therapeutics and Human Performance, 1e (Energy Medicine in Therapeutics & Human Performance) by James L. Oschman PhD (Author) Focusing on the wealth of information emerging in the area of energy medicine, this unique resource explores mechanisms by which mind and body processes influence the body's healing and performance potential. Content draws on an extraordinary range of sources to explore theories of human energy - from physiology and biophysics, to examples drawn from the realms of "spontaneous healing," cutting-edge athletic and artistic performance, the martial arts, and various contemplative and spiritual practices. Providing new insights and theoretical models, it offers ways to apply these concepts directly, practically, and clinically.Provides an understanding of the nature of energy medicine by exploring science and common experienceExplains complex scientific concepts in ways that are both vivid...
	Solar Energy Conversion: Dynamics of Interfacial Electron and Excitation Transfer (Rsc Energy and Environment Ser) by Piotr Piotrowiak (Editor), Laurie Peter (Editor), Heinz Frei (Editor), Tim S. Zhao (Editor), Ferdi Schuth (Editor) The importance of developing new, clean and renewable sources of energy will continue to grow in the foreseeable future and so will the need for the education of researchers in this field of research. The interest and challenges of the field continue to shift from simple homogeneous solutions to increasingly more complex heterogeneous systems and interfaces. Over the past decade there have been numerous theoretical and experimental breakthroughs many of which still exist only in the primary literature. The aim of this book is to gather in one volume the description of modern, sometimes exploratory, experimental and theoretical techniques applied to the dynamics of interfacial electron and electronic excitation transfer processes studied in the context of solar energy conversion. The...
	Charge and Energy Transfer Dynamics in Molecular Systems by Volkhard May (Author), Oliver Kühn (Author) This 3rd edition has been expanded and updated to account for recent developments, while new illustrative examples as well as an enlarged reference list have also been added. It naturally retains the successful concept of its predecessors in presenting a unified perspective on molecular charge and energy transfer processes, thus bridging the regimes of coherent and dissipative dynamics, and establishing a connection between classic rate theories and modern treatments of ultrafast phenomena.Among the new topics are:Time-dependent density functional theoryHeterogeneous electron transfer, e.g. between molecules and metal or semiconductor surfacesCurrent flows through a single molecule.While serving as an introduction for graduate students and researchers, this is equally must-have reading...
	Energy and Information Transfer in Biological Systems: How Physics Could Enrich Biological Understanding, Proceedings of the International Workshop Acireale, Catania, Italy 18 - 22 September 2002 by Francesco Musumeci (Editor), Larissa S. Brizhik (Editor), Mae-Wan Ho (Editor) This volume contains papers based on the workshop "Energy and Information Transfer in Biological Systems: How Physics Could Enrich Biological Understanding", held in Italy in 2002. The meeting was a forum aimed at evaluating the potential and outlooks of a modern physics approach to understanding and describing biological processes, especially regarding the transition from the microscopic chemical scenario to the macroscopic functional configurations of living matter. In this frame some leading researchers presented and discussed several basic topics, such as the photon interaction with biological systems also from the viewpoint of photon information processes and of possible applications; the influence of electromagnetic fields on the self-organization of biosystems including the...
	Technology Transfer for Renewable Energy: Overcoming Barriers in Developing Countries by Gill Wilkins (Author) This text highlights the role that renewable energy can play in achieving sustainable development. It focuses on rural areas of developing countries, looking in particular at stand-alone solar home systems and grid-connected biomass cogeneration plants. It analyzes the main barriers to the successful transfer of renewable energy technology, with case studies from a range of South-East Asian, South Asian, Pacific and African countries, and explains the ways in which these obstacles can be overcome. The roles of the key players involved and how the Kyoto Protocol can facilitate the transfer in order to mitigate climate change are also discussed.