Comparative study of distinct halide composites for highly efficient perovskite solar cells using a SCAPS-1D simulator.

This research investigates the influence of halide-based methylammonium-based perovskites as the active absorber layer (PAL) in perovskite solar cells (PSCs). Using SCAPS-1D simulation software, the study optimizes PSC performance by analyzing PAL thickness, temperature, and defect density impact on output parameters. PAL thickness analysis reveals that increasing thickness enhances JSC for MAPbI3 and MAPbI2Br, while that of MAPbBr3 remains steady. VOC remains constant, and FF and PCE vary with thickness. MAPbI2Br exhibits the highest efficiency of 22.05% at 1.2 µm thickness. Temperature impact analysis shows JSC, VOC, FF, and PCE decrease with rising temperature. MAPbI2Br-based PSC achieves the highest efficiency of 22.05% at 300 K. Contour plots demonstrate that optimal PAL thickness for the MAPbI2Br-based PSC is 1.2 µm with a defect density of 1 × 1013 cm-3, resulting in a PCE of approximately 22.05%. Impedance analysis shows the MAPbBr3-based PSC has the highest impedance, followed by Cl2Br-based and I-based perovskite materials. A comparison of QE and J-V characteristics indicates MAPbI2Br offers the best combination of VOC and JSC, resulting in superior efficiency. Overall, this study enhances PSC performance with MAPbI2Br-based devices, achieving an improved power conversion efficiency of 22.05%. These findings contribute to developing more efficient perovskite solar cells using distinct halide-based perovskite materials.

Phosphorus transport through subsurface drainage and surface runoff from a flat watershed in east central Illinois, USA.

A long-term water quality monitoring program was established to evaluate the effects of agricultural management practices on water quality in the Little Vermilion River (LVR) watershed, IL. This watershed has intensive random and irregular subsurface drainage systems. The objective of this study was to assess the fate and transport of soluble phosphorus (soluble P) through subsurface drainage and surface runoff. Four sites (sites A, B, C, and E) that had subsurface and surface monitoring programs were selected for this study. Three of the four study sites had corn (Zea mays L.) and soybeans (Glycine max L.) planted in rotations and the other site had seed corn and soybeans. Subsurface drainage and surface runoff across all sites removed an average of 16.1 and 2.6% of rainfall, respectively. Annual flow-weighted soluble P concentrations fluctuated with the precipitation, while concentrations tended to increase with high precipitation coupled with high application rates. The long-term average flow-weighted soluble P concentrations in subsurface flow were 102, 99, 194, and 86 microg L(-1) for sites A, B, C, and E, respectively. In contrast, the long-term average flow-weighted soluble P concentrations in surface runoff were 270, 253, 534, and 572 microg L(-1) for sites As, Bs, Cs, and Es, respectively. These values were substantially greater than the critical values that promote eutrophication. Statistical analysis indicated that the effects of crop, discharge, and the interactions between site and discharge and crop and discharge on soluble P concentrations in subsurface flow were significant (alpha = 0.05). Soluble P mass loads in surface runoff responded to discharge more consistently than in the subsurface flow. Subsurface flow had substantially greater annual average soluble P mass loads than surface runoff due to greater flow volume.

Watershed monitoring to address contamination source issues and remediation of the contaminant impairments.

The Big Blue River Basin is located in southeastern Nebraska and northeastern Kansas and consists of surface water in the Big Blue River, Little Blue River, Black Vermillion River, and various tributaries draining 24,968 km2. Approximately 75% of the land area in the basin are cultivated cropland. The Big Blue River flows into Tuttle Creek Reservoir near Manhattan, Kansas. Releases from the lake are used to maintain streamflow in the Kansas River during low flow periods, contributing 27% of the mean flow rate of the Kansas River at its confluence with the Missouri River. Tuttle Creek Reservoir and the Kansas River are used as sources of public drinking water and meet many of the municipal drinking water supply needs of the urban population in Kansas from Junction City to Kansas City. Elevated concentrations of pesticides in the Big Blue River Basin are of growing concern in Kansas and Nebraska as concentrations may be exceeding public drinking water standards and water quality criteria for the protection of aquatic life. Pesticides cause significant problems for municipal water treatment plants in Kansas, as they are not appreciably removed during conventional water treatment processes unless activated carbon filtering is used. Pesticides have been detected during all months of the year with concentrations ranging up to 200 microg/l. If high concentration in water is associated with high flow conditions then large mass losses of pesticides can flow into the water supplies in this basin. This paper will investigate the use of a monitoring program to assess the non-point source of this atrazine contamination. Several practices will be examined that have shown ability to remediate or prevent these impairments.