Band 2, Heft 6

Nitrogen doping is an effective way to tailor the properties of the shaped carbon materials, including the nanotubes, nanocups, nanofibers, as well as the nanorods, and render their potential use for various applications. The common bonding configurations obtained on the N insertion is the pyridinic N and pyrrolic N, which impart the characteristic properties to these carbon materials. This review will focus on the nitrogen-doped carbon materials, the doping effect on the electrochemistry of the doped nanomaterials, and the various synthetic methods to introduce N into the carbon network. The potential applications of the N-doped materials are also reviewed on the basis of the experimental and theoretical studies in electrochemistry.

Reducing supply voltage is a promising way to address the power dissipation in nano-electronic circuits. However, the fundamental lower limit of subthreshold slope (SS) within metal oxide semiconductor field effect transistors (MOSFETs) is a major obstacle to further scaling the operation voltage without degrading ON/OFF ratio in current integrated circuits. Tunnel field-effect transistors (TFETs) benefit from steep switching characteristics due to the quantum-mechanical tunneling injection of carriers from source to channel, rather than by conventional thermionic emission in MOSFETs. TFETs based on group III-V compound semiconductor materials further improve the ON-state current and reduce SS due to the low band gap energies and smaller carrier tunneling mass. The mixed arsenide/antimonide (As/Sb) In x Ga 1-x As/GaAs y Sb 1-y heterostructures allow a wide range of band gap energies and various staggered band alignments depending on the alloy compositions in the source and channel materials. Band alignments at source/channel heterointerface can be well modulated by carefully controlling the compositions of the mixed As/Sb material system. In particular, this review introduces and summarizes the progress in the development and optimization of low-power TFETs using mixed As/Sb based heterostructures including basic working principles, design considerations, material growth, interface engineering, material characterization, device fabrication, device performance investigation, band alignment determination, and high temperature reliability. A review of TFETs using mixed As/Sb based heterostructures shows superior structural properties and distinguished device performance, both of which indicate the mixed As/Sb staggered gap TFET as a promising option for high-performance, low-standby power, and energy-efficient logic circuit application.

The development of functional, biological solutions to repair or replace damaged tissues and organs is the goal of tissue engineering. This involves an interplay of cells, scaffolds and biomolecules that would generate a favourable response when implanted into patients, thus restoring functions lost or impaired due to injuries or diseases. Advances in nanotechnology have enabled the design and fabrication of novel materials at the nanometre scale. Hailed as the next generation of advanced materials, nanomaterials possess advantages of being biochemically and nanostructurally similar to that of physiological tissues. Moreover, nanotopological cues are incorporated, ensuring appropriate cellular responses, thereby enhancing the success of tissue regeneration. Nanobioceramics play a crucial role in bone tissue engineering due to its close chemical similarity to physiological bone and excellent biocompatibility. In addition, nanoscale engineering of these materials has the ability to enhance mechanical and biological properties. This review will begin with an introduction to nanomaterials and its associated considerations that should be taken into account. Next, the role of nanobioceramics achieving these considerations will be discussed. An overview of the current form of nanobioceramics being developed will be provided, concluding with an outlook of nanobioceramics for the healthcare industry.

Self-healing materials feature the outstanding ability of healing damage inflicted on them. This process leads to the (partial) restoration of the original properties of these materials, in particular of the mechanical properties. Several healing mechanisms involve processes on the nanoscopic level. These lead to the healing of the damage (e.g., crack or scratch) and, as a consequence, the macroscopic mechanical properties are reestablished. Moreover, self-healing of nanomaterials can also be achieved, which is of particular interest, because nanomaterials are particularly prone to damage due to their high surface volume ratio. This review summarizes the involvement of nanoscopic processes in the healing of macroscopic materials, and the healing of nanomaterials is discussed.

The field of nanotechnology has been widely recognized as comparable to biotechnology and digital information revolutions. As a general-purpose technology, nanotechnology is expected to have widespread applications across many critical industrial sectors. The growing market and competition require careful attention to intellectual property (IP) rights and strategies. The American patent system is currently going through the biggest reform since the passage of Patent Act of 1952, and many changes apply directly to the field of nanotechnology. This review discusses basic IP definitions, recent IP developments, and advanced protection strategies to better understand the status quo of IP specifically in nanotechnology. The potential impact from the patent system reform is also discussed.