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The increasing prevalence of health problems stemming from sedentary lifestyles and evolving workplace cultures has placed a substantial burden on healthcare systems. Consequently, remote health wearable monitoring systems have emerged as essential tools to track individuals' health and wellbeing. Self-powered triboelectric nanogenerators (TENGs) have exhibited significant potential for use as emerging detection devices capable of recognizing body movements and monitoring breathing patterns. However, several challenges remain to be addressed in order to fulfill the requirements for self-healing ability, air permeability, energy harvesting, and suitable sensing materials. These materials must possess high flexibility, be lightweight, and have excellent triboelectric charging effects in both electropositive and electronegative layers. In this work, we investigated selfhealable electrospun polybutadiene-based urethane (PBU) as a positive triboelectric layer and titanium carbide (Ti 3 C 2 T x ) MXene as a negative triboelectric layer for the fabrication of an energy-harvesting TENG device. PBU consists of maleimide and furfuryl components as well as hydrogen bonds that trigger the Diels−Alder reaction, contributing to its self-healing properties. Moreover, this urethane incorporates a multitude of carbonyl and amine groups, which create dipole moments in both the stiff and the flexible segments of the polymer. This characteristic positively influences the triboelectric qualities of PBU by facilitating electron transfer between contacting materials, ultimately resulting in high output performance. We employed this device for sensing applications to monitor human motion and breathing pattern recognition. The soft and fibrous-structured TENG generates a high and stable opencircuit voltage of up to 30 V and a short-circuit current of 4 μA at an operation frequency of 4.0 Hz, demonstrating remarkable cyclic stability. A significant feature of our TENG is its self-healing ability, which allows for the restoration of its functionality and performance after sustaining damage. This characteristic has been achieved through the utilization of the self-healable PBU fibers, which can be repaired via a simple vapor solvent method. This innovative approach enables the TENG device to maintain optimal performance and continue functioning effectively even after multiple uses. After integration with a rectifier, the TENG can charge various capacitors and power 120 LEDs. Moreover, we employed the TENG as a self-powered active motion sensor, attaching it to the human body to monitor various body movements for energy-harvesting and sensing purposes. Additionally, the device demonstrates the capability to recognize breathing patterns in real time, offering valuable insights into an individual's respiratory health.

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Titanium dioxide (TiO2) is widely applied in the field of pollution treatment due to its good catalytic properties and being an environmentally friendly material. In this study, TiO2 nanotubes were prepared from commercial TiO2 particles. The effects of carboxymethyl cellulose (CMC) and liquid glass (sodium silicate) on catalyst activity and catalyst adhesion on quartz tubes were investigated. Transmission microscopy (TEM), scanning microscope (SEM), X-ray diffraction (XRD), X-ray energy dispersive spectroscopy, Fourier transform infrared spectroscopy (FT-IR) were used for the characterization of the catalyst. In this study, the ethanol degradation ability of the catalyst, which was added with 0; 0.5; 1, and 1.5% liquid glass and calcined at 400 and 500oC, was determined. TiO2 nanotubes after preparation have a uniform diameter from 10-12 nm and an average length of about 150nm, specific surface area increases markedly compared to commercial granules (nearly 15 times). The results showed that CMC plays an important role in the thickness and distribution of TiO2 on the quartz surface. Liquid glass significantly affects the ethanol degradation efficiency.