Classic chemical sensors integrated in phones, vehicles, and industrial plants monitor the levels of humidity or carbonaceous/oxygen species to track environmental changes. Current projections for the next two decades indicate the strong need to increase the ability of sensors to sense a wider range of chemicals for future electronics not only to continue monitoring environmental changes but also to ensure the health and safety of humans. To achieve this goal, more chemical sensing principles and hardware must be developed. Here, a proof‐of‐principle for the specific electrochemistry, material selection, and design of a Li‐garnet Li7La3Zr2O12(LLZO)‐based electrochemical sensor is provided, targeting the highly corrosive environmental pollutant sulfur dioxide (SO2). This work extends the prime use of LLZO as a battery component as well as the range of trackable pollutants for potential future sensor‐noses. Novel composite sensing‐electrode designs using LLZO‐based porous scaffolds are employed to define a high number of reaction sites, and successfully track SO2at the dangerous levels of 0–10 ppm with close‐to‐theoretical SO2sensitivity. The insights on the sensing electrochemistry, phase stability and sensing electrode/Li+electrolyte structures provide first guidelines for future Li‐garnet sensors to monitor a wider range of environmental pollutants and toxins.
Computer‐free autonomous decision making based on environmental cues provides exciting alternatives to classic control systems for robots and smart materials. Although this functionality has been studied in microswimmers and active colloids where energy in the surrounding liquid is prevalent, there are no devices that can provide sufficient power from environmental chemicals to move and steer larger scale robots and vehicles in dry environments. This work overcomes this limitation with an environmentally controlled voltage source (ECVS) that, when directly attached to electric motors on a vehicle, can increase the energy available to the vehicle and provide computer‐free autonomous navigation toward chemical fuels in the environment and away from hazards. The ECVS uses electrochemistry to extract power from the chemical fuels, and the vehicle avoids hazards that reduce the output voltage or electrochemical kinetics. Two ECVSs can also be arranged in series or parallel to perform logical functions based on the chemicals in contact with the ECVSs. This work presents a new method to simultaneously steer and power vehicles and robots without computers by directly responding to a wide variety of chemical fields in their environment using electrochemistry.
- NSF-PAR ID:
- 10236181
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 5
- Issue:
- 4
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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