Graphene oxide quantum dots attached on wood-derived nanocellulose to fabricate a highly sensitive humidity sensor

Cellulose nanofibrils–graphene hybrids: recent advances in fabrication, properties, and applications

“…This type of hydrogel may open up new avenues to developing environmentally sensitive, self-assembly, high catalytic activity biomolecules for a wide range of applications. More recently, the humidity sensitivity of aerogels based on CNFs and GQDs, which display abundant oxygen-containing groups and large hydrophobic surface area, has been highlighted by Huang et al 24 The authors reported that dropping the dispersion containing both nanomaterials onto an interdigital electrode followed by lyophilization generates a high-performance capacitive humidity sensor. This efficiency is attributed to strong binding interactions such as hydrogen bonds and van der Waals forces between the fibrous CNFs and lamellar GQDs, hence generating a perforated and interconnected system with abundant active sites and migration channels for water molecules, as well as excellent homogeneity and uniformity, as shown in Fig.…”

“…Excellent information about graphene, its related derivatives, and their characteristics and potential applications has been reported. 17,[19][20][21][22][23][24][25][26][27][28] The global graphene market, which currently concerns semiconductor electronics, energy storage materials, and nanocomposites, is expected to reach >USD 876.8 million by 2027 with a growth rate estimate of >40% per year. 29 Nevertheless, GNMs still suffer from numerous shortcomings that need to be surpassed, such as the ease of the aggregation that causes the decrease of the surface area and drastically affects the optical, electrical, and mechanical features, as well as the low biocompatibility that mainly inhibits their employment in the biomedical area.…”

Humidity Sensors Based on Metal–Organic Frameworks

“…The interaction between the sensing materials and water molecules would affect the humidity−sensing properties, and a larger specific surface area and high porosity could expose more active sites [ 1 ]. In addition, pores or channels are known as the pathway for transporting water molecules [ 15 ]. Therefore, MOFs with a large specific surface area and high porosity are suitable for humidity sensing.…”

“…Thirdly, MOFs are stable. Humidity sensors that can work effectively for long periods of time are welcome, which requires the sensing materials to be highly stable [ 15 ]. The chemical bonds between the metal centers and the oxygen and nitrogen in the linkers endow the MOFs with good chemical stability, which is conducive to the preparation of highly stable MOF−based humidity sensors.…”

“…In addition, humidity−sensing properties such as response, sensitivity, linearity, hysteresis, response time, and long−term stability are highly related to the characteristics of sensing materials [ 11 , 12 , 13 , 14 ]. Normally, humidity−sensing materials are hydrophilic, porous, and stable [ 15 ]. Until now, humidity sensors based on different types of sensing materials such as metal oxides [ 12 ], polymers [ 16 , 17 , 18 , 19 , 20 ], and carbon materials [ 21 , 22 ] have been reported.…”