Search for: All records

Precise control of the life cycle of materials has become critical. Long-lasting materials are not always the best—for example, nondegradable plastic waste is now a serious environmental problem. Transient electronic devices have a prescribed life cycle in which all or part of the device can physically dissolve, disappear, or degrade after their utility ends. This concept creates compelling opportunities for biodegradable temporary, implantable electronics that do not require removal; environmentally benign biodegradable electronics with zero waste; and security hardware with on-time system destruction. Nanoscale materials provide new uses for transient materials dissolution by scaling up the rate of degradation; for example, a microscale Si single crystal is not dissoluble, but at around 100 nm, the Si single crystal dissolves in approximately one month. Significant advances have been made in exploring transient, water-soluble, and biodegradable nano-/micromaterials, and their degradation chemistry and kinetics. Advancing the state of the art in transient electronics requires contributions from many disciplines of materials science ranging from materials analysis to applications. This article outlines the history of transient electronics and briefly overviews concepts and issues from inorganic- and organic-based electronic materials, process technology, and energy devices to trigger transient electronics. 

Implantable neural interfaces are important tools to accelerate neuroscience research and translate clinical neurotechnologies. The promise of a bidirectional communication link between the nervous system of humans and computers is compelling, yet important materials challenges must be first addressed to improve the reliability of implantable neural interfaces. This perspective highlights recent progress and challenges related to arguably two of the most common failure modes for implantable neural interfaces: (1) compromised barrier layers and packaging leading to failure of electronic components; (2) encapsulation and rejection of the implant due to injurious tissue–biomaterials interactions, which erode the quality and bandwidth of signals across the biology–technology interface. Innovative materials and device design concepts could address these failure modes to improve device performance and broaden the translational prospects of neural interfaces. A brief overview of contemporary neural interfaces is presented and followed by recent progress in chemistry, materials, and fabrication techniques to improve in vivo reliability, including novel barrier materials and harmonizing the various incongruences of the tissue–device interface. Challenges and opportunities related to the clinical translation of neural interfaces are also discussed.