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The photovoltaic performances of n-i-p or inverted p-i-n BaSi₂ homojunction solar cells are limited by the parasitic high light absorption of n-BaSi₂ or p-BaSi₂ window layer. In this work, diverse electron transport materials (ETMs) and hole transport materials (HTMs) are employed instead of BaSi₂ as window layers to promote the performances of BaSi₂ solar cells, and the effects of different ETMs and HTMs were simulated and comprehensively studied. For n-ETM/i-BaSi₂/p-BaSi₂ solar cells, the solar cell with ZnO exhibits the highest efficiency of 28.21%. As increasing the thicknesses of ETM layer from 5nm to 100nm, the efficiency for n-BaSi₂/i-BaSi₂/p-BaSi₂ solar cell decreases seriously from 24.52% to 15.99%, while the solar cells with wide band gap ETMs including SnO₂, TiO₂ and ZnO show neglectable change in performances. The performances n-ETM/i-BaSi₂/p-BaSi₂ solar cells are affected by donor like defects more than acceptor like defects in i-BaSi₂. For p-HTM/i-BaSi₂/n-BaSi₂ solar cells, employing Cu₂O, CuI, CuSCN or NiO as HTM layer produces evident valence band discrepancies at HTM/i-BaSi₂ interfaces. Heavy doping in HTM layer is necessary desired to overcome the energy band barriers. As increasing the thicknesses of HTM layer from 5 nm to 100 nm, the efficiency for p-BaSi₂/i-BaSi₂/n-BaSi₂ solar cell also decreases from 24.52% to 15.99%, while the solar cells with wide band gap HTMs including CuI, CuSCN and NiO show neglectable change, and the efficiency for p-Cu₂O/i-BaSi₂/n-BaSi₂ solar cells decreases slightly from 25.86% to 24.88%. The performances of p-HTM/i-BaSi₂/n-BaSi₂ solar cells are affected by acceptor like defects more than donor like defects in i-BaSi₂.

The effects of hydrodynamic and mixing conditions on the variation of phytoplankton composition and their habitats were investigated in the tide-dominated macrotidal Chikugo River estuary during a neap-spring tidal cycle in 2021. The estuary changed from stratified to well-mixed conditions during a neap-spring transition. The river discharge was < 60 m³s^-1 during the study period. Seawater intruded towards 17 km (upstream) during neap tide and until 16 km during spring tide. Surface suspended sediment concentration (SSC) was low during neap tide and maximum (∼400 mg/L) during spring tide corresponding with changes in mixing and an estuarine turbidity maximum (ETM) was developed between 8-12 km during spring tide. Marine habitats diatoms were the major group with 20-89% of total phytoplankton. During a neap-spring tidal cycle, the maximum abundance of freshwater green algae was found during neap tide while diatoms (both marine and freshwater habitats) was in two days after neap tide and freshwater blue-green algae was in intermediate tide in response to changes in mixing conditions. The distribution of marine habitat diatoms and freshwater blue-green algae were positively correlated with salinity whereas freshwater green algae and freshwater habitat diatoms were negatively correlated with salinity. This study concludes that saltwater intrusion and mixing conditions driven by tidal forcing mainly controlled the species composition and their habitats in the Chikugo River estuary.