Flexible MXene films for batteries and beyond

MXenes add dozens of metallic conductors to the family of two-dimensional (2D) materials. A top-down synthesis approach removing A-layer atoms (e.g., Al, Si, and Ga) in MAX phases to produce 2D flakes attaches various surface terminations to MXenes. With these terminations, MXenes show tunable properties, promising a range of applications from energy storage devices to electronics, including sensors, transistors, and antennas. MXenes are also excellent building blocks to create flexible films used for flexible and wearable devices. This article summarizes the synthesis of MXene flakes and highlights aspects that need attention for flexible devices. Rather than listing the development of energy storage devices in detail, we focus on the main challenges of and solutions for constructing high-performance devices. Moreover, we show the applications of MXene films in electronics to call on designs to construct a complete system based on MXene with good flexibility, which consists of a power source, sensors, transistors, and wireless communications

Engineering mass transport properties in oxide ionic and mixed ionic electronic thin film ceramic conductors for energy applications

New emerging disciplines such as Nanoionics and Iontronics are dealing with the exploitation of mesoscopic size effects in materials, which become visible (if not predominant) when downsizing the system to the nanoscale. Driven by the worldwide standardisation of thin film deposition techniques, the access to radically different properties than those found in the bulk macroscopic systems can be accomplished. This opens up promising approaches for the development of advanced microdevices, by taking advantage of the nanostructural deviations found in nanometre sized, interface dominated materials compared to the ideal relaxed structure of the bulk. A completely new set of functionalities can be explored, with implications in many different fields such as energy conversion and storage, or information technologies. This manuscript reviews the strategies, employed and foreseen, for engineering mass transport properties in thin film ceramics, with the focus in oxide ionic and mixed ionic electronic conductors and their application in micro power sources

Nanotechnology in a Globalized World: Strategic Assessments of an Emerging Technology

PASCC Report Number 2014-006Nanotechnologies are enabling, dual-use technologies with the potential to alter the modern world significantly, from fields as wide-ranging as warfare to industrial design to medicine to social and human engineering. Seizing the technological lead in nanotech is often viewed as an imperative for both 21st century defense and global competitiveness. Only revolutionary technologies are believed to allow a country to take advantage of its relative backwardness—in the sense of its lack of commitment to existing, incremental technologies—and leap ahead of existing technological leaders in developing and deploying a revolutionary new technology. New technologies, however, are only likely truly to revolutionize an economy and society if there is a broader national base that allows a new technology to spread and transform from its initial niche application, whether civilian or military, and if society is willing to adopt the technology in question. Globally, there is significant belief in the revolutionary potential of nanotechnology, not only to transform warfare, economy and society, but also the international geopolitical hierarchy. Between 2001 and 2014, over sixty countries followed the United States and established nanotechnology initiatives. These countries range from advanced industrial countries in Europe to Japan to the emerging markets of Russia, China, Brazil, and India to developing countries such as Nepal and Pakistan.U.S. Naval Postgraduate School (NPS), Center on Contemporary Conflict (CCC), Project on Advanced Systems and Concepts for Countering WMD (PASCC