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W-doped In 2 O 3 (IWO) films prepared by reactive plasma deposition (RPD) technique at 150 °C have been studied to replace Sn-doped In 2 O 3 (ITO) serving as transparent electrodes for p-i-n structured perovskite solar cells. The optical and electrical properties of IWO films were found to depend on the oxygen partial pressure of deposition process. Compared with the reference ITO films, the IWO films obtained at an oxygen partial pressure of 0.12 Pa exhibited prominent performance, including higher near-infrared transmittance and carrier mobility. Furthermore, the IWO films showed higher work function than that of the ITO films, resulting in the enhancement of open-circuit voltage (0.982 V vs 0.901 V) and conversion efficiency (12.9 % vs 11.9 %). It can be attributed to that high work function of the IWO films reduced the carrier transport barrier at the interface between transparent electrode and PEDOT:PSS and enhanced the carrier collection near the edge of the perovskite bandgap. The excellent properties of the RPD-prepared IWO films indicate that it is a promising transparent electrode material for p-i-n structured perovskite solar cells, especially for applications requiring low-temperature fabrication. • IWO films fabricated by RPD method at 150 °C were developed and applied to p-i-n structured perovskite solar cells. • Compared with the reference ITO films, the IWO films showed higher near-infrared transmittance and carrier mobility. • The IWO film exhibited a higher work function than the reference ITO film, leading to improved V oc of perovskite solar cells. • The conversion efficiency of IWO-based solar cells was higher than that of ITO-based solar cells (12.9 % vs 11.9 %). [ABSTRACT FROM AUTHOR]

• Drought responses were measured for grass species on loamy and sandy soils. • Sandy soil is beneficial for plant growth but harmful for plant drought resistance. • Fibrous-rooted species might provide a buffer against drought in loamy soil. • Degraded grasslands with coarser soil might be more sensitive to drought. Grassland degradation is often accompanied by coarsened soil, which could change water and nutrient uptake by plant roots. Studying the effects of soil coarsening on species performance with different root systems under manipulated irrigation has important practical significance in grassland restoration under changing climate. We conducted a common garden experiment with three water treatments (control, drought stressed and water addition) and two soil texture (loamy soil which is fine and sandy soil which is coarse) under a rainout shelter to explore the effects of degradation on the growth and drought response of tap-rooted species and fibrous-rooted species. Three fibrous-rooted species (Setaira viridis , Cleistogenes squarrosa and Leymus chinensis) and three tap-rooted species (Medicago ruthenica , Artemisia frigida and Potentilla bifurca) were used in the study (P. bifurca failed to germinate). The results showed that three of the five selected species tended to have higher aboveground biomass, greater belowground biomass, larger height and longer root length in sandy soil than in loamy soil. For fibrous-rooted species, drought had negative influence on several plant traits in sandy soil, and had no influence on plant traits in loamy soil. For tap-rooted species, drought had negative influence on plant traits both in loamy soil and in sandy soil, and the influence was larger in loamy soil than in sandy soil. The results showed that loamy soil might provide a buffer against drought for fibrous-rooted species, but make tap-rooted species more sensitive to drought. Our results implied that degraded grasslands with coarsened soil might change community composition in the grassland, making tap-rooted species take the place of fibrous-rooted species. Thus, soil coarsening is an important factor in predicting drought resistance as well as composition of the community, and should be given more attention under future climate changes. [ABSTRACT FROM AUTHOR]

• Common garden experiments were conducted for 3 steppe species and 2 soils in China. • Plant traits shift obviously from early to late stage across the growing season. • H N distinguishes specie adaptability difference on degraded and nondegraded soils. • Artimisia frigida shows greater nitrogen stoichiometric homeostasis for shoot and root on degraded soil. • Our results explain the resistance of prevailing Artemisia frigida- steppe in China. The degraded grassland is characterized by changes in dominant species and decreased soil resource supply capacity, limiting community foraging by carbon capturing and/or resource absorption. In this study, we used a manipulative greenhouse experiment to explore the plant trait variations of three species representing three degradation succession stages in the Inner Mongolian grassland of China. We examined variability in key trait values during early, middle and late growing stages and assessed the nitrogen stoichiometric homeostasis (H N) of different plant organs growing on loamy (undegraded) and sandy (degraded) soils. The results showed that plant root length (RL) shifted significantly from the early to middle stage, where Artemisia frigida presented the longest RL, and Setaria viridis had the shortest RL. Leyums chinensis exhibited the largest root-shoot ratio (RSR) with a well-developed rhizome, while A. frigida had smaller but variable RSR which increased 1.57–2.15 times, changing from the resource acquisition to the resource conservation strategy from the early to late stage. The shoot nitrogen content (SNC) and root nitrogen content (RNC) decreased over the growing season. No obvious differences were observed between plant traits of L. chinensis or A. frigida when growing on loamy or sandy soils, despite the fact that the nutrient supply in loamy soil was better. Shoot H N showed higher values for plants growing on loamy soils than on sandy soils. The degradation indicator species A. frigida presented the highest shoot H N under sandy soil and held relatively stable root H N for both soils (6.71 vs 6.00), indicating a higher adaptability to sandy soils. Our results explained the occurrence of the stable degraded grassland dominated by A. frigida and could shed light on methods for its restoration. [ABSTRACT FROM AUTHOR]

Nanopatterned poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) layers fabricated by soft-nanoimprint were applied to CH3NH3PbBr3 (MAPbBr3) light-emitting diodes to enhance light extraction. The electric field distribution of MAPbBr3 devices with different periods of the nanopatterned PEDOT:PSS was calculated using the finite-difference time-domain method, demonstrating that the 400-nm period was more effective in improving light outcoupling. By integrating the nanopatterned PEDOT:PSS layer, the external quantum efficiency of the device increased from 6.5% to 10.3%. It can be attributed to the fact that the nanopatterned structure reduced the refractive index discontinuity at the interface between MAPbBr3 and PEDOT:PSS, thereby reducing light trapping in the waveguide mode. [ABSTRACT FROM AUTHOR]