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Abstract Silver nanowires (AgNWs) hold great promise for applications in wearable electronics, flexible solar cells, chemical and biological sensors, photonic/plasmonic circuits, and scanning probe microscopy (SPM) due to their unique plasmonic, mechanical, and electronic properties. However, the lifetime, reliability, and operating conditions of AgNW-based devices are significantly restricted by their poor chemical stability, limiting their commercial potentials. Therefore, it is crucial to create a reliable oxidation barrier on AgNWs that provides long-term chemical stability to various optical, electrical, and mechanical devices while maintaining their high performance. Here we report a room-temperature solution-phase approach to grow an ultra-thin, epitaxial gold coating on AgNWs to effectively shield the Ag surface from environmental oxidation. The Ag@Au core-shell nanowires (Ag@Au NWs) remain stable in air for over six months, under elevated temperature and humidity (80 °C and 100% humidity) for twelve weeks, in physiological buffer solutions for three weeks, and can survive overnight treatment of an oxidative solution (2% H 2 O 2 ). The Ag@Au core-shell NWs demonstrated comparable performance as pristine AgNWs in various electronic, optical, and mechanical devices, such as transparent mesh electrodes, surface-enhanced Raman spectroscopy (SERS) substrates, plasmonic waveguides, plasmonic nanofocusing probes, and high-aspect-ratio, high-resolution atomic force microscopy (AFM) probes. These Au@Ag core-shell NWs offer a universal solution towards chemically-stable AgNW-based devices without compromising material property or device performance.
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Advanced Neural Probe Sensors toward Multi‐Modal Sensing and Modulation: Design, Integration, and Applications
Abstract Neural probe devices have undergone significant advancements in recent years, evolving from basic single‐functional devices to sophisticated integrated systems capable of sensing, stimulating, and regulating neural activity. The neural probes have been demonstrated as effective tools for diagnosing and treating numerous neurological disorders, as well as for understanding sophisticated connections and functions of neuron circuits. The multifunctional neural probe platforms, which combine electrical, optical, and chemical sensing capabilities, hold promising potential for revolutionizing personalized healthcare through closed‐loop neuromodulation, particularly in the treatment of conditions such as epilepsy, Parkinson's disease, and depression. Despite these advances, several challenges remain to be further investigated, including biocompatibility, long‐term signal quality and stability, and miniaturization, all of which hinder their broader clinical application. This paper provides an overview of the design principles of the neural probe structures and sensors, fabrication strategies, and integration techniques for the advanced multi‐functional neural probes. Key electrical, optical, and chemical sensing mechanisms are discussed, along with the selection of corresponding functional materials. Additionally, several representative applications are highlighted, followed by a discussion of the challenges and opportunities that lie ahead for this emerging field.
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- PAR ID:
- 10571436
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Sensor Research
- Volume:
- 4
- Issue:
- 2
- ISSN:
- 2751-1219
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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