High-Performance Self-Powered NO ₂ Sensor With Nitrogen-Doped MOF-Derived In ₂ O ₃ Core-Shell Fiber Architecture

The development of wearable gas sensors requires advancing low-power sensing materials and integrating energy harvesting technologies for sustainable power supply. Here, a self-powered NO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> sensor is proposed, employing a high-performance nitrogen-doped metal-organic framework derived In<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (N-MOF-In<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub>) sensor and triboelectric nanogenerator (MTP-TENG) as its key components. The porous core-shell fiber-like N-MOF-In<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> is synthesized through a straightforward solvothermal method followed by annealing and NO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> exposure, achieving an exceptional response value (1460) and fast response/recovery time (320/220 s) to 1 ppm NO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> at room temperature. The remarkable performance metrics are attributed to the unique hierarchical porosity of the core-shell architecture and the reconstruction of surface electronic states resulting from effective nitrogen doping. Additionally, MTP-TENG is designed with a conductive network of multi-walled carbon nanotubes embedded in thermoplastic polyurethane and paired with a polytetrafluoroethylene film. The integration of the N-MOF-In<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> sensor with the MTP-TENG enables the conversion of a resistive signal into a pulsed voltage output, resulting in a 28% reduction in response time. This study provides a promising strategy for high-performance, self-powered NO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> detection at room temperature, contributing to the development of wearable gas-sensing devices.