Foreword
In the twenty-first century, humanity is facing serious and urgent issues of energy
depletion and environmental degradation. Due to rapid economic growth, we are
experiencing the most extensive energy shortages and environmental pollution in
history, also resulting in globally destructive climate change. While our industries
are constantly providing a variety of innovative new products and materials, it is
becoming imperative to focus on the recycling and treatment of waste materials as
well. Moreover, we need to reduce the consumption of natural resources and raise
awareness of the great impact of our consumerism so that the technologies, products,
and materials we develop are environmentally harmonious and sustainable.
Many of the recent Nobel prizes in physics and chemistry are related to photochemistry and catalytic chemistry as well as materials or systems related to these
areas. Photocatalysis which induces efficient and effective reactions at room temperature under sunlight irradiation has been the focus of much attention for its
potential to establish ideal technologies which can convert clean, safe, and abundant
solar energy into electrical and/or chemical energy.
In fact, in the last 45 years since the discovery of the sensitizing effect of a TiO 2
electrode for the electrolysis of water by Honda and Fujishima, much research has
been carried out on the development of semiconductor photocatalysis using various
metal oxide catalysts. New breakthrough technologies such as the separate production of H 2 and O 2 from water, CO 2 reduction with H 2 O, the transformation or
complete mineralization of organic molecules, reduction of heavy metal ions as
well as nontoxic deodorization, antisepsis, decontamination, and sterilization processes will be essential in the reduction or elimination of harmful compounds from
polluted air, water, and soil. This book brings to light much of the recent research in
the development of such semiconductor photocatalytic systems.
In order to prepare highly efficient and functional photocatalysts, their meticulous
design and construction are vital, and this book delves into molecular level investigations of their nanoscale structures as well as the mechanisms behind their
reactivity. Modification methods to improve their performance including
ion-doping, heterojunction structural development, noble metal deposition, and
v
In the twenty-first century, humanity is facing serious and urgent issues of energy
depletion and environmental degradation. Due to rapid economic growth, we are
experiencing the most extensive energy shortages and environmental pollution in
history, also resulting in globally destructive climate change. While our industries
are constantly providing a variety of innovative new products and materials, it is
becoming imperative to focus on the recycling and treatment of waste materials as
well. Moreover, we need to reduce the consumption of natural resources and raise
awareness of the great impact of our consumerism so that the technologies, products,
and materials we develop are environmentally harmonious and sustainable.
Many of the recent Nobel prizes in physics and chemistry are related to photochemistry and catalytic chemistry as well as materials or systems related to these
areas. Photocatalysis which induces efficient and effective reactions at room temperature under sunlight irradiation has been the focus of much attention for its
potential to establish ideal technologies which can convert clean, safe, and abundant
solar energy into electrical and/or chemical energy.
In fact, in the last 45 years since the discovery of the sensitizing effect of a TiO 2
electrode for the electrolysis of water by Honda and Fujishima, much research has
been carried out on the development of semiconductor photocatalysis using various
metal oxide catalysts. New breakthrough technologies such as the separate production of H 2 and O 2 from water, CO 2 reduction with H 2 O, the transformation or
complete mineralization of organic molecules, reduction of heavy metal ions as
well as nontoxic deodorization, antisepsis, decontamination, and sterilization processes will be essential in the reduction or elimination of harmful compounds from
polluted air, water, and soil. This book brings to light much of the recent research in
the development of such semiconductor photocatalytic systems.
In order to prepare highly efficient and functional photocatalysts, their meticulous
design and construction are vital, and this book delves into molecular level investigations of their nanoscale structures as well as the mechanisms behind their
reactivity. Modification methods to improve their performance including
ion-doping, heterojunction structural development, noble metal deposition, and
v