Smart facemask for wireless CO2 monitoring

The use of facemasks by the general population is recommended worldwide to prevent the spread of SARS-CoV-2. Despite the evidence in favour of facemasks to reduce community transmission, there is also agreement on the potential adverse effects of their prolonged usage, mainly caused by CO2 rebreathing. Herein we report the development of a sensing platform for gaseous CO2 real-time determination inside FFP2 facemasks. The system consists of an opto-chemical sensor combined with a flexible, battery-less, near-field-enabled tag with resolution and limit of detection of 103 and 140 ppm respectively, and sensor lifetime of 8 h, which is comparable with recommended FFP2 facemask usage times. We include a custom smartphone application for wireless powering, data processing, alert management, results displaying and sharing. Through performance tests during daily activity and exercise monitoring, we demonstrate its utility for non-invasive, wearable health assessment and its potential applicability for preclinical research and diagnostics.

Rechargeable Flexible Paper Battery using PAV, PSSPEDOT Polymer

The main idea of this research is to design a rechargeable paper battery from local cheap and available materials. The practical part is represented by adding Polyvinyl alcohol (PVA) to conductive polymer (PSS PEDOT) with adding different mineral salts for then study the quantum of electrical conductivity and heat influence on electrical conductivity and acidity factors of the Electrolyte solution.The next step was to produce a rechargeable, flexible battery manufactured from regular cellulose paper, sulfone, and ionic solution.The measurements were made using modern laboratory devices to study the electrical properties, conductivity, resistance (Hall Effect), and voltage quantum of the ionic solution. Through the results we obtained, we noticed an increase in the conductivity of the ionic solution when adding mineral salts. The voltage quantum of one battery ranged between 0.3-0.3 volts, also several batteries were connected in series, and the result was 1.8 volts. Manufactured paper batteries can be recharged with a direct current source and recover their efficiency marked up 98-99%.

High-performance Bi2O3-NC anodes through constructing carbon shells and oxygen vacancies for flexible battery-supercapacitor hybrid devices

A facile and efficient strategy of constructing carbon shells and oxygen vacancies is proposed, in order to improve specific capacity, rate capability and cycling stability of the Bi2O3 anode for the battery–supercapacitor hybrid device.