Publications

In this communication, we demonstrate for the first time that ultrathin graphitic carbon nitride (g-C₃N₄) nanosheets can serve as a low-cost, green, and highly efficient electrocatalyst toward the reduction of hydrogen peroxide. We further demonstrate its application for electrochemical glucose biosensing in both buffer solution and human serum medium with a detection limit of 11 μM and 45 μM, respectively.

The scalable production of hydrogen fuel through electrochemical water reduction needs efficient Earth-abundant electrocatalysts to make the whole water-splitting process more energy efficient. In this Article, we report that an Al-doped CoP nanoarray on carbon cloth (Al-CoP/CC) behaves as a durable hydrogen evolution electrocatalyst with superhigh activity in 0.5 M H₂SO₄. It demands a pretty low overpotential of 23 mV to drive a geometrical catalytic current density of 10 mA cm^-2, outperforming all reported non-precious metal catalysts. Density functional theory calculations reveal that Al-CoP has a more thermo-neutral hydrogen adsorption free energy than CoP. Notably, this Al-CoP/CC is also superior in activity and durability as a bifunctional catalyst for alkaline water electrolysis, and its two-electrode water electrolyser delivers 10 mA cm^-2 water-splitting current at a cell voltage of 1.56 V in 1.0 M KOH. This work offers us an attractive cost-effective catalyst electrode in water-splitting devices for large-scale production of hydrogen fuels.

Contagious diseases are the principal cause of mortality, particularly respiratory viruses, a real menace for public health and economic development worldwide. Therefore, timely diagnosis and treatments are the only life-saving strategy to overcome any epidemic and particularly the ongoing prevailing pandemic COVID-19 caused by SARS-CoV-2. A rapid identification, point of care, portable, highly sensitive, stable, and inexpensive device is needed which is exceptionally satisfied by sensor technology. Consequently, the researchers have directed their attention to employing sensors targeting multiple analyses of pathogenic detections across the world. Nanostructured materials (nanoparticles, nanowires, nanobundles, etc.), owing to their unique characteristics such as large surface-to-volume ratio and nanoscale interactions, are widely employed to fabricate facile sensors to meet all the immediate emerging challenges and threats. This review is anticipated to foster researchers in developing advanced nanomaterials-based sensors for the increasing number of COVID-19 cases across the globe. The mechanism of respiratory viral detection by nanomaterials-based sensors has been reported. Moreover, the advantages, disadvantages, and their comparison with conventional sensors are summarized. Furthermore, we have highlighted the challenges and future potential of these sensors for achieving efficient and rapid detection.

Oxygen-doped graphene (O-G) derived from sodium gluconate is identified as a promising candidate to effectively catalyze ambient electrohydrogenation of N₂ to NH₃. Electrochemical tests on O-G in 0.1 M HCl suggest a large NH₃ yield of 21.3 μg h^-1 mg_cat.^-1 and a high faradaic efficiency of 12.6% at -0.55 and -0.45 V vs. reversible hydrogen electrode, respectively, with strong electrochemical and structural stability in 0.1 M HCl. Density functional theory calculations reveal the NRR catalytic mechanism and suggest that both the C[double bond, length as m-dash]O and O-C[double bond, length as m-dash]O groups contribute more greatly to the NRR compared with the C-O group.

It is urgent but still remains challenging to boost the alkaline water oxidation activity of transition metal oxide electrocatalysts for applications. In this work, we report our recent finding that surface introduction of an amorphous nickel–borate (Ni-Bi) layer on a nickel oxide (NiO) nanosheet array on carbon cloth (NiO/CC) can greatly enhance its electrochemical water oxidation activity under alkaline conditions. In a 1.0 M KOH solution, the resulting core–shell NiO@Ni-Bi/CC shows superior electrochemical catalytic activity of only 290 mV to drive 10 mA cm–2, 100 mV less than that for NiO/CC. Meanwhile, this catalyst electrode shows great long-term durability for at least 25 h. The high activity can be ascribed to the Ni-Bi layer on NiO promoting NiOOH generation as the active species. This study provides us an abundant water oxidation catalyst in an alkaline water electrolysis device for high-performance, durable electrolytic hydrogen production.

Engineering visible light active photocatalytic systems for renewable energy production and environmental remediation has always been a promising technology to counter overall energy demands and pollution challenges. As a fascinating conjugated polymer graphitic carbon nitride (g-C3N4) has been developed as a hotspot in the research field as a metal-free semiconducting material with the appealing band gap of 2.7 eV. Recently, g-C3N4 has gained tremendous interest in photocatalytic wastewater abatement as well as for hydrogen (H2) generation, carbon dioxide (CO2) reduction, and pollutant degradation, under exposure to visible light. Plasmonic silver halides (AgX) such as AgCl, AgBr, and AgI as plasmonic photocatalyst have received immense research interest owing to their escalating photocatalytic efficacy and strong surface plasmon resonance effect (SPR). AgX is the photosensitive, broad bandgap semiconducting materials with effectual antimicrobial properties. This review summarizes the heterostructure of carbonaceous g-C3N4 with plasmonic AgX, to reduce the recombination of photo-generated charge carriers, thus enhancing the natural light absorption. g-C3N4 grafted AgX nanoarchitectures can be utilized for several potential applications, for instance, overall water splitting (OWS), CO2 conversion to hydrocarbon fuels, pollutant exclusion, and antibacterial disinfection. This review focuses on the evolution of g-C3N4 as well as AgX, facile, and synthetic routes for fabrication of g-C3N4 tailored AgX, construction of nano-junctions (AgX/g-C3N4) with various photocatalytic applications. Finally, we provided a viewpoint of current hassles and some perceptions of novel trends in this exciting as well as developing research arena.