Diabetes mellitus is a metabolic disorder in the endocrine system. This dreadful disease is found in all parts of the world and becoming a serious threat of mankind health. There are lots of chemical agents available to control and to treat diabetic patients, but total recovery from diabetes has not been reported up to this date. In addition to adverse effects, drug treatments are not always satisfactory in maintaining euglycemia and avoiding late stage diabetic complications. Alternative to these synthetic agents, plants provided a potential source of hypoglycemic drugs and are widely used in several traditional systems of medicine to prevent diabetes. Several medicinal plants have been investigated for their beneficial effect in different type of diabetes. Other alternative therapies such as dietary supplements, acupuncture, hydrotherapy, and yoga therapies less likely to have the side effects of conventional approaches for diabetes.

The fabrication of a superior-performance ultraviolet (UV) photodetector utilizing graphene quantum dots (GQDs) as a sensitization agent on a ZnO-nanorod/GaN-nanotower heterostructure has been realized. GQD sensitization displays substantial impact on the electrical as well as the optical performance of a heterojunction UV photodetector. The GQD sensitization stimulates charge carriers in both ZnO and GaN and allows energy band alignment, which is realized by a spontaneous time-correlated transient response. The fabricated device demonstrates an excellent responsivity of 3.2 × 10 3 A/W at −6 V and displays an enhancement of ∼265% compared to its bare counterpart. In addition, the fabricated heterostructure UV photodetector exhibits a very high external quantum efficiency of 1.2 × 10 6 %, better switching speed, and signal detection capability as low as ∼50 fW.

Vertically aligned GaN nanotowers (NTs) were grown on the Si (111) substrate by plasma-assisted molecular beam epitaxy to design a highly responsive ultraviolet (UV) photodetector. The UV detector fabricated on a bare GaN-NT array yielded highly sensitive and repeatable device characteristics attributed by high responsivity (R), low noise equivalent power (NEP), and a high external quantum efficiency (EQE) of 484.77 A/W, 1.76 × 10 −13 W.Hz -1/2 , and 1.85 × 10 5 %, respectively. Furthermore, the developed UV photodetector demonstrated fast response with excellent stability when functionalized with Au nanoparticles and ZnO nanorods. This hybridized GaN-NT-based device with ZnO nanorods and Au nanoparticles significantly accelerated the performance of the device where a prominent threeorder reduction under dark current is observed along with gigantic R, lower NEP, and an extremely enhanced EQE of 7042 A/W, 1.84 × 10 −14 W.Hz -1/2 , and 2.7 × 10 6 %, respectively. The mechanism elaborating the enhanced device performance with a localized surface plasmon effect has been discussed through an energy band diagram. The fabricated highly sensitive device can lead the path toward future optoelectronic applications of integrated III-nitride technology.

The fabrication of unique taper-ended GaN-Nanotowers structure based highly efficient ultraviolet photodetector is demonstrated. Hexagonally stacked, single crystalline GaN nanocolumnar structure (nanotowers) grown on AlN buffer layer exhibits higher photocurrent generation due to high quality nanotowers morphology and increased surface/volume ratio which significantly enhances its responsivity upon ultraviolet exposure leading to outstanding performance from the developed detection device. The fabricated detector display low dark current (~ 12 nA), high ILight/IDark ratio (> 104), fast time-correlated transient response (~ 433 µs) upon ultraviolet (325 nm) illumination. A high photoresponsivity of 2.47 A/W is achieved in self-powered mode of operation. The reason behind such high performance could be attributed to built-in electric field developed from a difference in Schottky barrier heights will be discussed in detail. While in photoconductive mode, the responsivity is observed to be 35.4 A/W @ − 3 V along with very high external quantum efficiency (~ 104%), lower noise equivalent power (~ 10–13 WHz−1/2) and excellent UV–Vis selectivity. Nanotower structure with lower strain and dislocations as well as reduced trap states cumulatively contributed to augmented performance from the device. The utilization of these GaN-Nanotower structures can potentially be useful towards the fabrication of energy-efficient ultraviolet photodetectors.

The genetic resources of Allium in India are potential source of genes for widening the crop genetic base. Despite their high economic value, limited number of germplasm accessions of wild species have been collected and conserved mainly due to difficult access to areas of occurrence. The present work mainly highlights information on species diversity distribution and utilization of wild Allium species to assess the value of Indian germplasm and prioritization for future collection and conservation programmes.