Energy Harvesting Using Cotton Fabric Embedded with 2D Hexagonal Boron Nitride

Abstract

Continuous health monitoring through sensitive physiological signals (using a wearable device) is crucial for the early detection of heart diseases and breathing problems. Here, we have developed a flexible hBN/cotton hybrid device that can detect minor signals such as heartbeat and breathed-out air pressure. Systematic observation of the real-time motion sensing showed a peak-to-peak voltage output of ∼1.5 V for each heart rate pulse. The as-fabricated device showed a high voltage output of up to ∼10 V upon applying a pressure of ∼3 MPa. The FTIR results and DFT calculation suggested a chemical interaction between hBN and cellulose, giving rise to flat band characteristics and partially filled σ-bonding (sp2) hybridization. The atomic-scale chemical interface between atomically thin hBN and surface functional groups present on cotton resulted in charge localization and enhanced output voltage. An hBN/cotton hybrid device can bring new insights and opportunities to develop a self-charging and health-monitoring energy-harvesting cloth.

Energy Harvesting Using ZnO Nanosheet-Decorated 3D-Printed Fabrics

“…Previously, several efforts were devoted to the fabrication of energy harvesting devices using different flexible substrates such as cotton, polymers, papers, etc. However, preparing of highly sensitive devices with stability is still a challenge . Taking advantage of the distinct architecture with high flexibility, as a proof-of-concept, the 3DP architecture was used to measure the responses by utilizing it in the padded shoulder strap of the school bag under both the conditions, standing (static) and walking (dynamic) (Figure a).…”

“…Therefore, it confirms the increasing interlayer interaction between ZnO and fabric with increasing normal strain. When the polymer comes in contact with ZnO nanosheets with increasing pressure, charge transfer takes place at the interface. , Further, to understand the change in the contribution of ZnO and polymer to the conduction band (CB) with increasing strain, we plotted the charge density diagram of the conduction band minimum (CBM) at a particular K -point (Figure c,h). The contribution of PLA electronic states in CBM is less than that of the ZnO.…”

Antibacterial, UV-Protective, Hydrophobic, Washable, and Heat-Resistant BN-Based Nanoparticle-Coated Textile Fabrics: Experimental and Theoretical Insight

“…Hexagonal BN NPs were obtained by chemical vapor deposition (CVD) in a vertical reactor with induction heating by the interaction of ammonia with boron oxide vapor (BO, B 2 O 2 ) formed as a result of thermal dissociation of the boron oxide precursor (B/MgO/FeO = 3.5:0.1:1). 23 The synthesis temperature was 1430 °C. The gas flow rates were set to 300 (Ar) and 100 cm 3 / min (NH 3 ).…”

“…A 2D h-BN-and cotton-based sensor was developed and used to monitor the heart rate and exhaled air pressure. 23 When developing NP-decorated textile materials, it is necessary to ensure stable binding of NPs to the fabric surface since their loss can lead not only to a deterioration in properties but also to irritation or allergic reactions when NPs penetrate the body through skin pores. 24,25 The use of organic compounds containing functional groups for the NP pre-treatment can significantly improve their distribution over the carrier surface as well as increase the biocompatibility and stability of the textile materials.…”

“…Owing to a weak interlayer interaction (van der Waals forces) and covalent and partially ionic bonds in the plane, two-dimensional (2D) h -BN NPs exhibit piezoelectric properties. A 2D h -BN- and cotton-based sensor was developed and used to monitor the heart rate and exhaled air pressure …”