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Photo-microbes are well known to demolish rice and fruits, as farmers use chemical pesticides to overcome agricultural problems and economic damage. The use of pesticides in agriculture fails to protect crops in lower concentrations and increases the intake of chemicals that cause many human ailments. The sophisticated nanotechnology approach used in agriculture for antimicrobial activities offers several advantages for growth and improves nutrient absorption in plants. We report the green synthesis of silver nanoparticles (AgNPs) using Azadirachta indica (A. indica) and Mangifera indica (M. indica) tree leaf extract that contains antioxidants to treat numerous diseases. AgNPs tested against three plant pathogens, fungi Alternaria alternata (A. alternata), Sclerotium rolfsii (A. rolfsii), and bacteria Xanthomonas oryzae (X. oryzae), which leads to agricultural problems. The experiment was performed with different concentrations of AgNPs in μL/mL prepared using two other plants extract against fungi and bacteria during summer. The results expose the importance of plant extract in synthesizing silver nanoparticles (AgNPs) and their efficacy for microbes. A comparison among different concentrations of AgNPs (4 μL/mL, 6 μL/mL, and 10 μL/mL) was performed for two fungi (tomato disease) and bacteria (rice leaf blight disease). A-AgNPs (A. indica-AgNPs) demonstrate a greater zone of inhibition than M-AgNPs (M. indica-AgNPs), further highlighting the dependence of plants. Under in vitro conditions, the results of the antifungal activity showed zones of inhibition of 21 mm against A. alternata and 17 mm against A. rolfsii, while antibacterial activity against X. oryzae bacteria showed a 15 mm zone of inhibition at 10 mg/mL for A-AgNPs, and less for M-AgNPs. For AgNPs, the antifungal activity was characterized bya more significant area of inhibition than antibacterial activity was. The current study indicates that AgNPs with lower concentrations exhibitsuperior toxicity to microbes and may be able to manage diseases in rice and tomato, and increase plant growth.

Perovskite solar cells (PSCs) have shown power conversion efficiency (PCE) up to 25.5%, but they are still struggling with their poor environmental stability. We have improved the ecological stability of un-encapsulated PSCs via interface modification of the top metal electrode. We used CH3NH3PbI3-xClx perovskite as the light absorber and Ag metal as the top electrode. The interface of Ag electrode was modified by introducing a thin layer of MoOx/Al before Ag. We observed that MoOx/Al interlayer before Ag imparts better stability to the devices than conventional Ag electrode only. We found that MoOx/Al interlayer impedes the diffusion of oxygen and metal electrode into the perovskite film and considerably halts the device degradation upon being kept for about 350 h under laboratory ambient conditions (room temperature 25±2oC and humidity 40±5%). This work mainly highlights the role of interfaces in PSCs degradation, and will help to address the stability issues in PSCs.

Synthesis of titanium dioxide nanoparticles (TiO2 NPs) has been done by sol-gel-hydrothermal colloidal route in two different apparatus; one being simple stainless steel (named as TiO2-B) and other being at constant temperature and pressure autoclave (named as TiO2-W). These TiO2 NPs were investigated by various characterization techniques such as scanning electron microscope (SEM), X-ray diffractometer (XRD), and photoluminescence spectrophotometer. Also, it was observed that the quality of the synthesized TiO2-W NPs is comparable with the commercial TiO2 NPs (TiO2-C), whereas the cost of synthesis is almost reduced to half. The synthesized TiO2 NPs are used as the photoanode in dye-sensitized solar cell (DSSC). DSSC with TiO2-W showed better power conversion efficiency as compared to DSSC with TiO2-B.