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Faormamadinium based perovskites have been proposed to replace the methylammonium lead tri-iodide (MAPbI 3 ) perovskite as the light absorbing layer of photovoltaic cells owing to their photo-active and chemically stable properties. However, the crystal phase transition from the photo-active α -FAPbI 3 to the non-perovksite δ -FAPbI 3 still occurs in un-doped FAPbI 3 films owing to the existence of crack defects, which degrads the photovoltaic responses. To investigate the crack ratio (CR)-dependent structure and excitonic characteristics of the polycrystalline FAPbI 3 thin films deposited on the carboxylic acid functionalized ITO/glass substrates, various spectra and images were measured and analyzed, which can be utilized to make sense of the different devices responses of the resultant perovskite based photovoltaic cells. Our experimental results show that the there is a trade-off between the formations of surface defects and trapped iodide-mediated defects, thereby resulting in an optimal crack density or CR of the un-doped α -FAPbI 3 active layer in the range from 4.86% to 9.27%. The decrease in the CR (tensile stress) results in the compressive lattice and thereby trapping the iodides near the PbI 6 octahedra in the bottom region of the FAPbI 3 perovskite films. When the CR of the FAPbI 3 film is 8.47%, the open-circuit voltage (short-circuit current density) of the resultant photovoltaic cells significantly increased from 0.773 V (16.62 mA cm -2 ) to 0.945 V (18.20 mA cm -2 ) after 3 d. Our findings help understanding the photovoltaic responses of the FAPbI 3 perovskite based photovoltaic cells on the different days., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

We report on the formation of bendable and edge-on poly[3-(4-carboxybutyl)thiophene-2,5-diyl] (P3CT) polymers thin layer used as a hole modification layer (HML) in the inverted perovskite solar cell. The aggregations of 2D layer-like P3CT polymers in dimethylformamide (DMF) solution can be formed via aromatic π - π stacking interactions and/or hydrogen-bonding interactions with the different concentration from 0.01 to 0.02 wt%, which highly influences the photovoltaic performance of the inverted perovskite solar cells. The atomic-force microscopic images and water droplet contact angle images show that the P3CT polymers modify the surface properties of the transparent conductive substrate and thereby dominating the formation of perovskite crystalline thin films, which play important roles in the highly efficient and stable perovskite solar cells. It is noted that the V OC ( J SC ) of the encapsulated solar cells values are maintained to be higher than 1.115 V (22 mA cm -2 ) after 104 d when an optimized π - π stacked and hydrogen-bonded P3CT polymer is used as the HML. On the other hand, the solar cell showed a high long-term stability by maintaining 85% of the initial power conversion efficiency in the ambient air for 103 d., (© 2023 IOP Publishing Ltd.)

Calla lily ( Zantedeschia aethiopica (L.) Spreng.) is an important ornamental crop used in garden landscapes, floral arrangements, and medicinal applications. Gibberellic acid (GA 3 ) is actively involved in cell elongation, growth, physiology, and flowering. In addition, it is an environmentally-friendly compound which can be applied to plants to increase the ornamental production. Therefore, the present study was designed with three GA 3 spray times viz., single, double and triple spray and five exogenous applications of gibberellic acid concentrations viz., 0, 25, 50, 100, and 200 mg L -1 with factorial randomized block design. Results revealed that the interaction effect of combinations of two time applications of GA 3 at 100 mg L -1 induced higher growth parameters over control. Significantly higher physiological parameters viz., photosynthetic rate (14.3 μmol m -2 s -1 ), number of stomata (26.5 mm -2 ), stomatal conductance (0.28 mmol m -2 s -1 ), and transpiration rate (3.6 mmol m -2 s -1 ) were reported when plants were treated twice with 100 mg L -1 GA 3 . Similarly, among flowering traits, days to flower were significantly low in plants treated two-time spray at GA 3 100 mg L -1 (169.8 days). The number of flowers in the double spray at GA 3 100 mg L -1 treatment increased by 11.3 and 23.7% over triple spray and control, respectively. Vase life was also significantly higher in plants treated with double spray at GA 3 100 mg L -1 (6.3 days). The regression equation and correlation matrix indicated a strong relationship between growth, flowering and GA 3 concentrations up to 100 mg L -1 . The PCA analysis revealed that the calla lily crop is positively affected by spray timing and GA 3 treatments. In the context of vegetative, reproductive, and longevity parameters of the crop, a dual spray of 100 mg L -1 GA 3 can be recommended to small scale farmers and commercial growers as an alternative technique for promoting growth, yield and improving the ornamental value for commercial level production., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The grain sizes of soft CH 3 NH 3 PbI 3 (MAPbI 3 ) thin films and the atomic contact strength at the MAPbI 3 /P3CT-Na interface are manipulated by varying the drying time of the saturated MAPbI 3 precursor solutions, which influences the device performance and lifespan of the resultant inverted perovskite photovoltaic cells. The atomic-force microscopy images, cross-sectional scanning electron microscopy images, photoluminescence spectra and absorbance spectra show that the increased short-circuit current density ( J SC ) and increased fill factor (FF) are mainly due to the formation of merged MAPbI 3 grains. Besides, the open-circuit voltage ( V OC ) of the encapsulated photovoltaic cells largely increases from 1.01 V to 1.15 V, thereby increasing the power conversion efficiency from 17.89% to 19.55% after 30 days, which can be explained as due to the increased carrier density of the MAPbI 3 crystalline thin film. It is noted that the use of the optimized drying time during the spin coating process results in the formation of merged MAPbI 3 grains while keeping the contact quality at the MAPbI 3 /P3CT-Na interface, which boosts the device performance and lifespan of the resultant perovskite photovoltaic cells., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Gladiolus (Gladiolus grandiflorus Andrews) is a high-valued bulbous cut flower. However, the shorter postharvest life of the gladiolus, limits its marketing and commercial value. In the present investigation, the effect of lemon grass (LG) essential oil as an antimicrobial agent was studied towards increasing the vase life of gladiolus. The results revealed that as compared to control (distilled water), treatment with a lower concentration of 5 µL L -1 LG essential oil prolonged the vase life of gladiolus up to 11 days (d). Scanning Electron Microscope (SEM) observation indicated that the sample treated with 5 µL L -1 LG essential oil showed intact vasculature, suggesting reduced microbial blockage at the stem end which was further corroborated by microbial count. Biochemical analysis suggested an increased level of total soluble sugars, carotenoid content, lower MDA accumulation, and higher activity of antioxidant enzymes in LG treated flowers. Moreover, transcripts levels of genes associated with senescence viz., GgCyP1 and GgERS1a were downregulated, while expression of GDAD1 and antioxidant genes such as GgP5C5, GgPOD 1, GgMnSOD, and GgCAT1 were upregulated in LG treated cut spikes as compared to control. Among various treatments we have concluded that, the vase life of the gladiolus cut spike was improved along with the relative fresh flower weight and diameter of flower at the lower dose of 5 µL L -1 LG oil in the vase solution. Thus, LG oil as an eco-friendly agent has the potential to extend the postharvest life of cut flowers., (© 2023. The Author(s).)

The bird of paradise ( Strelitzia reginae L.) is one of the important tropical cut flowers. Generally, flowers like bird of paradise (BOP) grown for the commercial ornamental market must be of high pre and postharvest quality. Thus, to improve the postharvest longevity and increase marketability, the relative efficacy of two different biologically synthesized nanoparticles (NPs) was evaluated. The novel proprietary stimulants were graphene oxide (GO) and silver nanoparticles (SNPs). The NP treatments were applied as a vase (lower concentrations) solutions. Among all the applied treatments, the synergistic effect of GO + SNPs at 1 µL L -1 vase solution significantly ( p =0.05) prolongs the post-harvest life of cut flowers of BOP. Increased vase life over the deionized water (DI) control was associated with better maintenance of relative water uptake, relative fresh weight, suppressed microbial density at stem-end and delay of stem blockage, reduced electrolyte leakage, malondialdehyde (MDA), SOD, and POD activity. In contrast to control, administration of NPs gave better results for all analyzed parameters. Application of biologically synthesized NPs in combination (GO + SNPs at 1 µL L -1 ) extended the vase life of cut flowers by 6 days compared with control flowers, and overall, showed better results than the control. The findings of the studies revealed that the standardized NPs could have more potential in prolonging the postharvest life of cut flowers in BOP. Thus, this technique can be used as a novel postharvest technology for commercial application in cut flowers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Thakur, Chandel, Guleria, Verma, Kumar, Singh, Rakwal, Sharma and Bhargava.)

The properties of CH 3 NH 3 PbI 3 (MAPbI 3 ) crystalline thin films and the device performance of highly efficient MAPbI 3 photovoltaic cells are investigated by varying the temperature of the antisolvent from 20 °C to 50 °C during the washing enhanced nucleation (WEN) process. The surface, structural, optoelectronic and defect properties of the perovskite thin films are characterized through atomic-force microscopy, X-ray diffractometry and photoluminescence spectrometry. The experimental results show that changing the temperature of the antisolvent during the WEN process can manipulate the MAPbI 3 crystalline thin films from the (110)-(002) complex phase to a (002) preferred phase. It is noted that the highest power conversion efficient of the inverted MAPbI 3 photovoltaic cells is 19.30%, mainly due to the increased carrier collection efficiency and reduced carrier recombination when the temperature of the antisolvent is 30 °C., (© 2022 IOP Publishing Ltd.)

Atomic-force microscopic images, x-ray diffraction patterns, Urbach energies and photoluminescence quenching experiments show that the interfacial contact quality between the hydrophobic [6,6]-phenyl-C 61 -buttric acid methyl ester (PCBM) thin film and hydrophilic CH 3 NH 3 PbI 3 (MAPbI 3 ) thin film can be effectively improved by using a binary antisolvent mixture (toluene:dichloromethane or chlorobenzene:dichloromethane) in the anti-solvent mixture-mediated nucleation process, which increases the averaged power conversion efficiency of the resultant PEDOT:PSS (P3CT-Na) thin film based MAPbI 3 solar cells from 13.18% (18.52%) to 13.80% (19.55%). Beside, the use of 10% dichloromethane (DCM) in the binary antisolvent mixture results in a nano-textured MAPbI 3 thin film with multicrystalline micrometer-sized grains and thereby increasing the short-circuit current density and fill factor (FF) of the resultant solar cells. It is noted that a remarkable FF of 80.33% is achieved, which can be used to explain the stable photovoltaic performance without additional encapsulations., (© 2021 IOP Publishing Ltd.)

The averaged power conversion efficiency of polyelectrolytes (P3CT-Na) based MAPbI 3 solar cells can be increased from 14.94% to 17.46% with a wetting method before the spin-coating process of MAPbI 3 precursor solutions. The effects of the wetting process on the surface, structural, optical and excitonic properties of MAPbI 3 thin films are investigated by using the atomic-force microscopic images, x-ray diffraction patterns, transmittance spectra, photoluminescence spectra and Raman scattering spectra. The experimental results show that the wetting process of MAPbI 3 precursor solution on top of the P3CT-Na/ITO/glass substrate can be used to manipulate the molecular packing structure of the P3CT-Na thin film, which determines the formation of MAPbI 3 thin films., (© 2021 IOP Publishing Ltd.)

A high-efficiency inverted-type CH 3 NH 3 PbI 3 (MAPbI 3 ) solar cell was fabricated by using a ultrathin poly[3-(4-carboxybutyl)thiophene-2,5-diyl]-Na (P3CT-Na) film as the hole transport layer. The averaged power conversion efficiency (PCE) can be largely increased from 11.72 to 18.92% with a double-filtering process of the P3CT-Na solution mainly due to the increase in short-circuit current density ( J SC ) from 19.43 to 23.88 mA/cm 2 , which means that the molecular packing structure of P3CT-Na thin film can influence the formation of the MAPbI 3 thin film and the contact quality at the MAPbI 3 /P3CT-Na interface. Zeta potentials, atomic-force microscopic images, absorbance spectra, photoluminescence spectra, X-ray diffraction patterns, and Raman scattering spectra are used to understand the improvement in the J SC . Besides, the light intensity-dependent and wavelength-dependent photovoltaic performance of the MAPbI 3 solar cells shows that the P3CT-Na thin film is not only used as the hole transport layer but also plays an important role during the formation of a high-quality MAPbI 3 thin film. It is noted that the PCE values of the best P3CT-Na based MAPbI 3 solar cell are higher than 30% in the yellow-to-near infrared wavelength range under low light intensities. On the other hand, it is predicted that the double-filtering method can be readily used to increase the PCE of polymer based solar cells.

Deterioration of indoor air quality (IAQ) has become a serious concern as people spend lots of time indoors and prolonged pollution exposure can result in adverse health outcomes. Indoor plants can phytoremediate a wide variety of indoor contaminants. Nonetheless, few experiments have demonstrated their efficacy in real-time environments. Therefore, the present study aims to experimentally assess the efficiency of Areca palm potted plants in phytoremediation of primary indoor air pollutant viz. total volatile organic compounds (TVOCs), carbon dioxide (CO 2 ), and carbon monoxide (CO) levels from real-world indoor spaces, for the first time. Four discrete naturally ventilated experimental sites (I-IV) situated at the Council of Scientific and Industrial Research- Institute of Himalayan Bioresource Technology (CSIR-IHBT) were used. For over a period of 4 months, the sites were monitored using zero plants as a control (1-4 week), three plants (5-8 week), six plants (9-12 week), and nine plants (13-16 week), respectively. Present results indicate that Areca palm potted plants can effectively reduce the TVOCs, CO 2 , and CO levels by 88.16% in site IV, 52.33% and 95.70% in site III, respectively. The current study concluded that Areca palm potted plants offer an efficient, cost-effective, self-regulating, sustainable solution for improving indoor air quality and thereby human well-being and productivity in closed and confined spaces.

The power conversion efficiency (PCE) of single-junction solar cells was theoretically predicted to be limited by the Shockley-Queisser limit due to the intrinsic potential loss of the photo-excited electrons in the light absorbing materials. Up to now, the optimized GaAs solar cell has the highest PCE of 29.1%, which is close to the theoretical limit of ~33%. To pursue the perfect photovoltaic performance, it is necessary to extend the lifetimes of the photo-excited carriers (hot electrons and hot holes) and to collect the hot carriers without potential loss. Thanks to the long-lived hot carriers in perovskite crystal materials, it is possible to completely convert the photon energy to electrical power when the hot electrons and hot holes can freely transport in the quantized energy levels of the electron transport layer and hole transport layer, respectively. In order to achieve the ideal PCE, the interactions between photo-excited carriers and phonons in perovskite solar cells has to be completely understood., Competing Interests: The authors declare no conflict of interest.