Graphene-Based Nanocomposites for Energy Storage

Since the first report of using micromechanical cleavage method to produce graphene sheets in 2004, graphene/graphene-based nanocomposites have attracted wide attention both for fundamental aspects as well as applications in advanced energy storage and conversion systems. In comparison to other materials, graphene-based nanostructured materials have unique 2D structure, high electronic mobility, exceptional electronic and thermal conductivities, excellent optical transmittance, good mechanical strength, and ultrahigh surface area. Therefore, they are considered as attractive materials for hydrogen (H2) storage and high-performance electrochemical energy storage devices, such as supercapacitors, rechargeable lithium (Li)-ion batteries, Li–sulfur batteries, Li–air batteries, sodium (Na)-ion batteries, Na–air batteries, zinc (Zn)–air batteries, and vanadium redox flow batteries (VRFB), etc., as they can improve the efficiency, capacity, gravimetric energy/power densities, and cycle life of these energy storage devices. In this article, recent progress reported on the synthesis and fabrication of graphene nanocomposite materials for applications in these aforementioned various energy storage systems is reviewed. Importantly, the prospects and future challenges in both scalable manufacturing and more energy storage-related applications are discussed

Synthesis and characterization of hierarchical Ti3C2Tx MXene/graphitic-carbon nitride/activated carbon@luffa sponge composite for enhanced water desalination

In this study, advanced solar steam technologies are explored for their potential applications in seawater desalination and wastewater purification. We have developed a three-dimensional photothermal evaporator using MXene, luffa sponge (LS), graphitic-carbon nitride (GCN) and activated carbon (AC). The hierarchical Ti3C2Tx MXene/GCN/AC@LS composite photothermal evaporator exhibits superior thermostability, pH stability, and mechanical durability. The Ti3C2Tx MXene/GCN/AC@LS composite evaporator having a dimension of 1.25 cm displays excellent performance, leading to a high evaporation rate of 2.6 kg m−2h−1 and a high solar-thermal conversion efficiency of 96 % under 1 sun illumination. This high efficiency is attributed to the good light absorption by the Ti3C2Tx MXene/GCN/AC@LS composite coupled with a better wetting through the internal microchannels of the LS, which envisages a faster water delivery and evaporation of water. The Ti3C2Tx MXene/GCN/AC@LS composite captures the residual heat from the sidewall surface as an additional source of energy

SARS-CoV-2-on-Chip for Long COVID Management

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a “wicked evil” in this century due to its extended progression and huge human mortalities. Although the diagnosis of SARS-CoV-2 viral infection is made simple and practical by employing reverse transcription polymerase chain reaction (RT-PCR) investigation, the process is costly, complex, time-consuming, and requires experts for testing and the constraints of a laboratory. Therefore, these challenges have raised the paradigm of on-site portable biosensors on a single chip, which reduces human resources and enables remote access to minimize the overwhelming burden on the existing global healthcare sector. This article reviews the recent advancements in biosensors for long coronavirus disease (COVID) management using a multitude of devices, such as point-of-care biosensors and lab-on-chip biosensors. Furthermore, it details the shift in the paradigm of SARS-CoV-2-on-chip biosensors from the laboratory to on-site detection with intelligent and economical operation, representing near-future diagnostic technologies for public health emergency management

Synthesis of titanium carbide (TiC) using recycled precursor for potential scale-up of low-cost MXene

In this study, we report the low-cost synthesis of titanium carbide (TiC) from recycled precursors and further used to synthesize MAX phase material, Ti 3AlC 2. The recycled precursor, carbon extracted from the used tyres using a few processes is used to synthesize TiC with high purity. The use of tyre-derived carbon offers several environmental benefits such as facile synthesis, low cost, environment-friendly, etc. The as-synthesized TiC is further used as a precursor to synthesize low-cost Ti 3AlC 2. The structure of TiC and Ti 3AlC 2 are characterized by UV–visible spectroscopy and X-ray diffraction analysis. The microstructure and surface morphology of the samples are examined using scanning electron microscope imaging and energy-dispersive X-ray spectroscopy. The chemical bonding information is analyzed by Fourier transform infrared spectroscopy and the thermal behaviour of the samples are examined using thermogravimetric analysis. The successful cost-effective synthesis of TiC and Ti 3AlC 2 are confirmed from XRD analysis and the samples show high purity. TiC and Ti 3AlC 2 show excellent thermal stability which helps in their potential applications in the future. This study proclaims a new strategy to synthesize low-cost Ti 3AlC 2 MXene for the large-scale production using TiC precursor where the TiC precursor is synthesized using carbon precursor