Cellulosic graphene: growth, characterization, and fabrication toward ambient humidity sensing

ABSTRACT

Monitoring environmental humidity using a sensitive, cost-effective device is a contemporary challenge. Considering various sensing materials, graphene has functioned as a best-suitable material for humidity sensing because of its favorable characteristics, for example, large reactive surface area (highly sensitive), better electrical conductivity (fast response of water adsorption), etc. A straightforward and bio-acceptable approach to growing multilayer graphene was formed by the thermal exfoliation process of cellulosic materials. The crystallite size, inter-layer distance, number of layers, crystalline defects, and crystalline planes orientation for synthesized cellulosic-graphene materials were characterized from X-ray diffraction (XRD) analysis, Raman spectroscopy, and High-resolution transmission electron microscopy (HRTEM). Additionally, the elemental analysis was provided by Energy-dispersive X-ray (EDX) spectroscopy. A market-ready product on humidity sensor was fabricated and studied the different parameters associated with sensing mechanism, for example, hysteresis effect with different temperature, effect on impedance with relative humidity, sensitivity, etc. The fabricated device’s better response time and stability may be observed with commercially available humidity sensors (HIH5030 and DHT11H).

KEYWORDS:

• Cellulosic film
• graphene
• humidity sensor
• onion peel
• thermal exfoliation
• hysteresis
• sensitivity
• stability
• response time
• nanomaterials

Disclosure statement

No potential conflict of interest was reported by the author(s).