The fundamental processes taking place in metals under extreme conditions can occur on ultrafast timescales (i.e., nanoseconds to picoseconds), and yet their result can continue to have a significant impact on the structural properties for many years to follow. The challenge in developing in situ methods for characterization under extreme conditions therefore involves both the modification of the instrumentation to implement the high-temperature, strain, and radiation conditions and the definition of the timescale over which the measurement must be made. While techniques are well established for characterization of the long-term effects of extreme conditions, experiments are only just beginning to probe the initial stages of structural evolution. This article reviews recent developments in optical, x-ray, and electron probes of metals under extreme conditions and also discusses the needs for future experiments and potential pathways to achieving these goals.

Individual nanotubes made of carbon, boron nitride, iron, silicon, or other materials have properties such as high strength, toughness, electrical and thermal conductivity, and light weight that cannot be matched by conventional materials. Nanotubes also change their properties in response to external fields and change one type of energy into another, which are useful for design. This article explores three main steps in exploiting responsive materials based on nanotubes: nanotube synthesis, macroscale material fabrication, and incorporation into device structures for novel applications. Nanotubes are always synthesized as individual particles in the form of powders, smoke particles, or aligned forests. To be industrially important, nanotubes generally must be processed to form derivative materials such as functionalized/coated powders and forests and macroscale intermediate materials such as sheets, ribbon, and yarn. The processed nanotubes are then used to develop responsive materials and devices that are able to resist, react to, or generate energy from their environment. This article provides background information and ideas on how to develop nanotube responsive materials for everyday use.

The idea of first-principles methods is to determine the properties of materials by solving the basic equations of quantum mechanics and statistical mechanics. With such an approach, one can, in principle, predict the behavior of novel materials without the need to synthesize them and create a virtual design laboratory. By showing several examples of new electrode materials that have been computationally designed, synthesized, and tested, the impact of first-principles methods in the field of Li battery electrode materials will be demonstrated. A significant advantage of computational property prediction is its scalability, which is currently being implemented into the Materials Genome Project at the Massachusetts Institute of Technology. Using a high-throughput computational environment, coupled to a database of all known inorganic materials, basic information on all known inorganic materials and a large number of novel “designed” materials is being computed. Scalability of high-throughput computing can easily be extended to reach across the complete universe of inorganic compounds, although challenges need to be overcome to further enable the impact of first-principles methods.

Materials scientists involved in synthesis are exceptionally skilled at designing and constructing individual molecules with the goal of introducing rationally tailored chemical and physical properties. However, the task of assembling such special molecules into organized, supramolecular structures with precise, nanometer-level organizational control to execute specific functions presents a daunting challenge. Soft and hard matter suitable for unconventional types of electronic circuitry represents a case in point and, in principal, offer capabilities not readily achievable with conventional silicon electronics. In this context, “unconventional” means circuitry that can span large areas, can be mechanically flexible and/or optically transparent, can be created by large-scale, high-throughput fabrication techniques, and has atomic-level tunability of properties. In the process of preparing, characterizing, and fabricating prototype devices with such materials, we learn many new things about the electronic and electrical properties of the materials and the interfaces between them. This account briefly overviews recent progress in three interconnected areas: (1) organic semiconductors for complementary π-electron circuits, (2) soft matter high-κ gate dielectrics for organic and inorganic electronics, and (3) metal-oxide semiconductors as components in such devices. Space limitations allow only touching upon selected highlights in this burgeoning field.