New, inexpensive and non-polluting energy technologies are of great importance for civilization. A promising source is solar energy, which can be photocatalytically converted into gaseous fuel or electricity. It has been hypothesized that nanomaterials may lead to improved photoelectrochemical (PEC), suspended photocatalytic, and photovoltaic cells. This particular field of study is vast considering the various ways nanomaterials can be synthesized, manipulated, and employed. Here, several different nanomaterials are studied as photocatalysts and as components in photoelectrochemical and photovoltaic cells. The purpose is to better understand charge transfer properties and energetics of these materials, and eventually, to help find a cheap, active, and sustainable photocatalyst for our ever-increasing energy demands. Chapter 1 gives a brief introduction to the field of nanomaterials for solar energy conversion. The motivation for this research is given, water-splitting photocatalysis is explained, and the various ways nanomaterials can be employed are reviewed. Chapter 2 explains how nanomaterials such as titanium dioxide and tungsten oxide can be used to photocatalytically decompose organic contaminants in wastewater while simultaneously producing electricity. Efficiency and power output analysis of derived photoelectrochemical cells revealed the highest published values for titanium dioxide electrodes under 395 nm illumination. Chapter 3 discusses calcium niobate (TBACa2Nb3O10, TBA = tetrabutylammonium) nanosheets as a photocatalyst for hydrogen evolution from aqueous methanol solution under UV illumination. Photoelectrochemical techniques were used to study the effects of ion modification of TBACa2Nb3O10 on the energetics, specifically the position of the Fermi energy. The data shows a direct relationship between the position of the Fermi energy and the relative rate of hydrogen production. Chapter 4 explains the fabrication and function of the first fractal electrode-based organic photovoltaic cells. Although the fractal electrode enhances the interfacial area between the light absorber and electrode, enhanced charge recombination results in reduced photocurrent for fractal silver. Chapter 5 gives a selection of the photoelectrochemical properties of iridium dioxide nanoparticles and single-crystal tungsten oxide nanosheets. The data can be used to calculate the photo-onset values for each material. Chapter 6 gives supporting information on calculating the power conversion efficiency of a PEC cell.

Troy Townsend's thesis explores the structure, energetics and activity of three inorganic nanocrystal photocatalysts. The goal of this work is to investigate the potential of metal oxide nanocrystals for application in photocatalytic water splitting, which could one day provide us with clean hydrogen fuel derived from water and solar energy. Specifically, Townsend's work addresses the effects of co-catalyst addition to niobium oxide nanotubes for photocatalytic water reduction to hydrogen, and the first use of iron oxide 'rust' in nanocrystal suspensions for oxygen production. In addition, Townsend studies a nickel/oxide-strontium titanate nanocomposite which can be described as one of only four nanoscale water splitting photocatalysts. He also examines the charge transport for this system. Overall, this collection of studies brings relevance to the design of inorganic nanomaterials for photocatalytic water splitting while introducing new directions for solar energy conversion.

This book mainly focuses on the solar energy conversion with the nanomaterials. It describes the applications on two dimensional carbon nanomaterials: graphene and graphdiyne. Also, works on conductive polymer and bio-inspired material is included. The work described here is the first few reports on the applications of graphene, which becomes one of the hottest materials nowadays. This work also proves and studies the charge transfer between the semi-conductor and graphene interface, which is benefit to the applications in solar cells and photocatalysis. At the same time, method to synthesize and assemble the given nanomaterials (TiO2 nanosheets, gold nanoparticles, graphene, PS-PAA, PANI) is detailed, which is easier to the readers to repeat the experiments.

As our world’s population is constantly growing, so also is the need to power the growth and spread of technology. The conversion of abundant solar energy into useable sources of fuel is an area of significant and vital research. Photocatalytic water splitting via suspended nanomaterials or photoelectrochemical cells has great promise for this purpose. This research focuses on the preparation and analysis of nanomaterials utilizing simple methods and earth abundant chemicals that will lead to cost-competitive methods to convert solar energy into an easily stored and transported fuel source. Specifically, our research seeks to better understand the methods of charge generation and separation in nanomaterial films and to quantify the limits of activity in suspended photocatalysts. Chapter 2 introduces a study on the nature of photovoltage generation in well-ordered hematite films under zero applied bias. The thickness of Fe2O3 nanorod films is varied by a simple hydrothermal synthesis and confirmed with TEM and profilometry measurements. Surface photovoltage spectroscopy (SPS) in the presence of air, water, nitrogen, oxygen, and under vacuum confirms photovoltages are associated with oxidation of surface water and hydroxyl groups and with reversible surface hole trapping on the 1 minute time scale and de-trapping on the 1 hour time scale with a maximum photovoltage of -130 mW under 2.0 eV – 4.5 eV illumination. Sacrificial donors (KI, H2O2, KOH) increase the voltage to -240 and -400 mW, due to improved hole transfer. The photovoltage is quenched with the addition of co-catalysts CoO[subscript x] and Co-Pi, possibly due to the removal of surface states and enhanced e/h recombination. Chapter 3 outlines a methodical exploration of the limits of water oxidation from illuminated ß-FeO(OH) suspensions. Well-defined akaganéite nanocrystals are able to produce oxygen gas from aqueous solutions in the presence of an appropriate electron acceptor. Optimal conditions were achieved by systematically varying the amount of catalyst, concentration of the electron acceptor, pH of the solution, and light intensity. A decrease in activity is shown to be the result of particle agglomeration after roughly 5 hours of illumination. A maximum O2 evolution rate of 35.2 μmol O2 h−1 is observed from an optimized system, with a QE of 0.19%, and TON of 2.58 based on total ß-FeO(OH). Chapter 4 continues to understand charge separation and transport in CdS nanorods. These nanomaterials are capable of catalytic proton reduction under visible illumination, but suffer from photo-corrosion resulting in decreased H2 production. SPS measurements show a maximum photovoltage of -230 mV at 2.75 eV and the charge separation is largely reversible. Coating the rods with graphitic carbon nitride (g-C3N4) creates a hole accepting protective layer than prevents oxidative loss of photo-activity. By adding platinum salts, additional photovoltage could be extracted through field induced charge migration from excited sub gap defect states and trap sites. The addition of a sacrificial reagent would either decrease or increase the photovoltage (depending on the reagent used) by creating additional bias in the films or charge recombination pathways. Finally, it was shown that varying the substrate has an effect on the platinum/substrate polarized charge injection. Chapter 5 Surface photovoltage is used to show for the first time the charge separation properties of Sn2TiO4, an n-type photocatalyst, a series of cuprous niobium oxides doped with tantalum (CuNb[subscript 1-y]Ta[subscript y]O[subscript x]), and a Cu (I) tantalum oxide Cu5Ta11O3.

An essential resource for scientists designing new energy materials for the vast landscape of solar energy conversion as well as materials processing and characterization Based on the new and fundamental research on novel energy materials with tailor-made photonic properties, the role of materials engineering has been to provide much needed support in the development of photovoltaic devices. Advanced Energy Materials offers a unique, state-of-the-art look at the new world of novel energy materials science, shedding light on the subject’s vast multi-disciplinary approach The book focuses particularly on photovoltaics, efficient light sources, fuel cells, energy-saving technologies, energy storage technologies, nanostructured materials as well as innovating materials and techniques for future nanoscale electronics. Pathways to future development are also discussed. Critical, cutting-edge subjects are addressed, including: Non-imaging focusing heliostat; state-of-the-art of nanostructures Metal oxide semiconductors and their nanocomposites Superionic solids; polymer nanocomposites; solid electrolytes; advanced electronics Electronic and optical properties of lead sulfide High-electron mobility transistors and light-emitting diodes Anti-ferroelectric liquid crystals; PEEK membrane for fuel cells Advanced phosphors for energy-efficient lighting Molecular computation photovoltaics and photocatalysts Photovoltaic device technology and non-conventional energy applications Readership The book is written for a large and broad readership including researchers and university graduate students from diverse backgrounds such as chemistry, materials science, physics, and engineering working in the fields of nanotechnology, photovoltaic device technology, and non-conventional energy.

Among electrode materials, inorganic materials have received vast consideration owing to their redox chemistry, chemical stability, high electrochemical performance, and high-power applications. These exceptional properties enable inorganic-based materials to find application in high-performance energy conversion and storage. The current advances in nanotechnology have uncovered novel inorganic materials by various strategies and their different morphological features may serve as a rule for future supercapacitor electrode design for efficient supercapacitor performance. Inorganic Nanomaterials for Supercapacitor Design depicts the latest advances in inorganic nanomaterials for supercapacitor energy storage devices. Key Features:  Provides an overview on the supercapacitor application of inorganic-based materials.  Describes the fundamental aspects, key factors, advantages, and challenges of inorganic supercapacitors.  Presents up-to-date coverage of the large, rapidly growing, and complex literature on inorganic supercapacitors.  Surveys current applications in supercapacitor energy storage.  Explores the new aspects of inorganic materials and next-generation supercapacitor systems.

Renewable and Clean Energy Systems Based on Advanced Nanomaterials: Basis, Preparation and Applications describes the fundamental aspects of a diverse range of nanomaterials used in the fields of renewable and clean energy. Various methods of preparing several different nanomaterials for green energy systems, such as advanced nanomaterials for solar cells, mixed metal oxide-based nanomaterials for hydrogen storage, and active nanomaterials for Li ion batteries are presented along with their advantages, disadvantages, and applications. Chapters also discuss novel methods of power analysis, frequency regulation methods, practical applications of solar panels, economic efficiency of solar energy, solar physics, and much more.This is a valuable resource on the basic science, preparation methods, and practical applications of advanced nanomaterials for green energy systems. - Features recent advances on nanomaterials preparation methods and their applications in photovoltaic technology - Discusses sustainable strategies for producing large-scale nanomaterials, focusing on preparation techniques that are cost-effective and eco-friendly - Reviews the efficiency of nanomaterials used in solar energy storage and conversion

This book provides a comprehensive overview of the latest developments and materials used in electrochemical energy storage and conversion devices, including lithium-ion batteries, sodium-ion batteries, zinc-ion batteries, supercapacitors and conversion materials for solar and fuel cells. Chapters introduce the technologies behind each material, in addition to the fundamental principles of the devices, and their wider impact and contribution to the field. This book will be an ideal reference for researchers and individuals working in industries based on energy storage and conversion technologies across physics, chemistry and engineering. FEATURES Edited by established authorities, with chapter contributions from subject-area specialists Provides a comprehensive review of the field Up to date with the latest developments and research Editors Dr. Mesfin A. Kebede obtained his PhD in Metallurgical Engineering from Inha University, South Korea. He is now a principal research scientist at Energy Centre of Council for Scientific and Industrial Research (CSIR), South Africa. He was previously an assistant professor in the Department of Applied Physics and Materials Science at Hawassa University, Ethiopia. His extensive research experience covers the use of electrode materials for energy storage and energy conversion. Prof. Fabian I. Ezema is a professor at the University of Nigeria, Nsukka. He obtained his PhD in Physics and Astronomy from University of Nigeria, Nsukka. His research focuses on several areas of materials science with an emphasis on energy applications, specifically electrode materials for energy conversion and storage.

The handbook comprehensively covers the field of inorganic photochemistry from the fundamentals to the main applications. The first section of the book describes the historical development of inorganic photochemistry, along with the fundamentals related to this multidisciplinary scientific field. The main experimental techniques employed in state-of-art studies are described in detail in the second section followed by a third section including theoretical investigations in the field. In the next three sections, the photophysical and photochemical properties of coordination compounds, supramolecular systems and inorganic semiconductors are summarized by experts on these materials. Finally, the application of photoactive inorganic compounds in key sectors of our society is highlighted. The sections cover applications in bioimaging and sensing, drug delivery and cancer therapy, solar energy conversion to electricity and fuels, organic synthesis, environmental remediation and optoelectronics among others. The chapters provide a concise overview of the main achievements in the recent years and highlight the challenges for future research. This handbook offers a unique compilation for practitioners of inorganic photochemistry in both industry and academia.

Metal-Organic Framework Nanocomposites: From Design to Application assembles the latest advances in MOF nanocomposites, emphasizing their design, characterization, manufacturing, and application and offering a wide-ranging view of these materials with exceptional physical and chemical properties. FEATURES Discusses various types of MOF materials, such as polyaniline MOF nanocomposites, magnetic MOF nanocomposites, and carbon nanotube-based MOF nanocomposites Includes chapters on the usage of these materials in pollutant removal, electrochemical devices, photocatalysts, biomedical applications, and other applications Covers different aspects of composite fabrication from energy storage and catalysts, including preparation, design, and characterization techniques Emphasizes the latest technology in the field of manufacturing and design Aimed at researchers, academics, and advanced students in materials science and engineering, this book offers a comprehensive overview and analysis of these extraordinary materials.