The rapid development of electronics has caused the accumulation of electronic waste that is threatening the environment and human health. The deployment of the Internet of Things (IoT), enabled by 5G microwave communication technology, will involve an increasing number of electronic devices. Microwave communication devices consist of petroleum/ceramic-based substrates and metallic traces that are non-biodegradable. Here, we report a smart, flexible, and transient organic microwave resonator (TOMR) using cellulose nanofibrils (CNF) nanopaper as substrate and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) as conducting trace. The device produced a resonant profile with the maximum transmission coefficient (S21) amplitude of −14.95 dB at a resonant frequency of 2.75 GHz under ambient conditions (20 °C, 30% relative humidity (RH)). The TOMR demonstrated sensing capabilities, wherein increasing the %RH modulated the device’s resonant amplitude (-29 mdB/%RH from 0% to 50% RH and −90 mdB/%RH from 50% to 90% RH) and resonant frequency (3600 kHz/%RH). Moreover, the PEDOT:PSS trace could be reclaimed, recycled, and redeposited on a CNF nanopaper, which enabled the fabrication of a TOMR that displayed a similar resonant profile. Hence, this study demonstrates the first transient organic microwave resonator embedded with sensing capabilities and introduces a framework to minimize the environmental impact of 5G microwave communication devices for the IoT.
We are happy to announce our Ph.D Candidate, Nicole Tratnik, won 5th place in the student poster competition at the SPE,EAV Plastics in Electric & Autonomous Vehicles Conference. Her poster was titled, “Enhanced sustainability of upcycleable biobased epoxy vitrimers with designed recyclability” and was based off of her recently published paper that can be found here. Congrats Nicole!
A new article from Ning Yan’s lab has been published in Industrial Crops and Products written by Chuanwei Zhang, Pengfei Zhang, Yanhui Li, S. Nair Sandeep, Jianyong Li, Maocheng Ji, Sixian Peng, Ning Yan, and Fangyi Li.
Through a single-sided cavity free-form foaming process, composites with open cell structures similar to wood cells were obtained by using corn starch, pulp fiber, and sisal fibers, which was used as the middle layer of the sandwiched composites. Afterwards, more hydrophobic lignin-containing nanocellulose fibrils from pine bark were coated on the surfaces of the open cell composites by high-pressure gun spraying, simulating the bark of wood to impart barrier property to the final product. The water barrier, mechanical property, apparent density, heat insulation, and biodegradability of the sandwich structured bio-composites were characterized. Experimental results indicated that the water contact angle on the surface of the bio-composite was as high as 92°. The apparent density of the bio-composite was very low, at 0.107 g/cm3. The tensile strength of the bio-composites reached 5.3 MPa. After conducting biodegradability tests in soil for 60 days, the bio-composites lost 87 % of its mass.
A new article out of a collaboration between Dr. Ning Yan and Dr. Jing Chen’s labs has been published in the Journal of Environmental Chemical Engineering written by Xiaojun Zhang, Jialong Wu, Manxiang Wu, Lianfu Wang, Dayu Yu, Ning Yan, Huiming Wu, Jin Zhu, and Jing Chen.
Owing to their versatility, fluorescent carbon quantum dots (CQDs) have attracted significant attention for applications in sensors, bioimaging, microfluidics, photodynamic therapy, drug delivery, light-emitting diode, etc. Herein, nitrogen and lanthanum co-doped multifunctional lignin-based carbon quantum dots ((N, La)-CQDs) were prepared from enzymatic hydrolysis lignin using a simple one-step hydrothermal method. The diameter of the CQDs obtained was about 2.2 nm with a good water solubility at the excitation wavelength of around 365 nm and emission wavelength of around 465 nm. This is the first discovery of (N, La)-CQDs to detect Sn2+. (N, La)-CQDs were successfully used to detect Fe3+, Sn2+, and ClO– ions in the range of 0–100 μM with the detection limits of 0.99 μM, 1.1 μM and 1.1 μM sequentially, and the linear fit R2 of 0.9997, 0.9943 and 0.9941 respectively. Non-cytotoxic (N, La)-CQDs can be used for labeling cells and detecting Sn2+ in zebrafish. These attractive features make these non-toxic, environmentally friendly CQDs material highly promising for applications in a wide range of areas, such as biomedicine, biosensing, disease diagnosis, and environmental monitoring.