High‐efficiency antimony selenosulfide (Sb2(S,Se)3) solar cells are often fabricated by hydrothermal deposition and also comprise a CdS buffer layer. Whereas the use of toxic materials such as cadmium compounds should be avoided, both of these issues hinder scaling up to large areas and market access. For this reason, co‐sublimation is studied as a manufacturing process for the active layer as well as the use of Cd‐free buffer layers. To further improve the power conversion efficiency (PCE), a graded bandgap profile is designed for the absorber layer. A V‐shaped graded bandgap in the Sb2(S,Se)3 absorber layer is produced on a TiO2 substrate by co‐sublimation of a controlled varying molar ratio of Sb2Se3 and Sb2S3. Moreover, increasing the Se/S ratio improves the grain size and favorable (hk1) orientations, reduces the detrimental bulk defects in Sb2(S,Se)3 films. Consequently, the optimized Sb2(S,Se)3 solar cells reach a PCE of 9.02%, which is a record value for Cd‐free Sb‐based solar cells. A PCE of 7.15% is further demonstrated for a Sb2(S,Se)3 monolithically interconnected minimodule with an active area of 12.32 cm2. This co‐sublimation graded bandgap technique provides a useful guidance for the optimization of a range of solar cells based on alloy compounds.

Band Gap and Defect Engineering for High‐Performance Cadmium‐free Sb2(S,Se)3 Solar Cells and Modules

Aiming to the global energy insecurity due to extensive dependence on fossil fuels, hydrogen is supposed to provide relief by researchers. However, employed to combustion engines, this green fuel leaves hazardous NOx and limits output due to low volumetric energy content. Hence, improving operating parameters like compression ratio and manifold pressure, and NOx mitigating technique like EGR may prove a boon. Therefore, in the present study, combustion and NOx emission behavior of the SI-engine is studied under variable manifold air pressure (MAP) (up to 130 kPa) and EGR (up to 15%) at compression ratio 14:1. The outcomes shows the flame development increased by 1.24%, while flame propagation is increased by 1.63% by MAP boosting due to increased air and fuel supply. Cylinder pressure and heat-release rate (HRR) are also surged due to the increased fuel supply to maintain excess-air ratio (λ). However, peak cylinder pressure is retarded due to elongated combustion. The exhaust gas temperature (EGT) is increased by 19.4%, while elevated Tmax is observed to shoot up NOx by 40%. Combustion in improved at low EGR due to reduced λ, and also the specific NOx. At higher EGR rate deteriorated combustion due to increased heterogeneity by high dilution, increasing combustion duration, cooling losses and reducing cylinder pressure, Tmax and EGT. A 9.33% and 5.67% increase in CA10 and CA10–90 respectively is observed for 130 kPa at 15% EGR than no EGR. The rapid reduction in oxygen and higher heterogeneity reducing residence time, resulted in rapid drop (33% at N/A to 42.68% at 130 kPa for 15% EGR) in NOx by EGR. The coefficient variation is reduced by boosting MAP but increased severely at higher EGR, which restricts operating EGR rate.

Studying the effects of manifold pressure boosting and EGR on combustion and NOx emission of hydrogen-fueled SI engine

Assessment of air management strategies to improve the transient response of advanced gasoline engines operating under high EGR conditions

Synthesis and characterization of Cu-sandwiched Sb2Se3 thin films and numerical simulation of p-Sb2Se3/n-ZnSe heterojunction solar cell

Antimony selenide (Sb2Se3) solar cells often demonstrate current–voltage (J–V) distortion at low temperature, particularly at reverse bias or under red‐light irradiation. A highly doped p‐type (HDP) thin layer between the buffer and absorber layers is typically supposed to induce the J–V distortion. In this work, an analytical model for the experimental Sb2Se3 solar cell has been presented to investigate the effect of the HDP layer characteristics on the J–V distortion. This proposed model can also calculate the critical voltage at which the J–V distortion occurs. The results show that the Sb2Se3 solar cells with the HDP layer have low efficiency when doping concentration and thickness of the HDP layer increase due to a large J–V distortion. This study confirms that the presence of an electron barrier in the conduction band formed by the HDP layer can cause J–V distortion. Hence, the effect of electron barrier height on cell performance based on the derived formulas is investigated. Finally, comparing the simulation and modeling results with variations of the physical and electrical properties of the HDP layer provides a good evaluation for understanding the behavior of Sb2Se3 solar cells.

An Analytical Model for Sb2Se3 Thin‐Film Solar Cells by Considering Current‐Voltage Distortion

Interpenetrating structure for efficient Sb2Se3 nanorod array solar cells loaded with CuInSe2 QDs sensitizer

Combined effects of electric supercharger and LP-EGR on performance of turbocharged engine

There are currently no standard treatments for chronic atrophic gastritis and traditional Chinese medicine may be effective. This study aims to investigate the efficacy and safety of Weierkang pills in treating chronic atrophic gastritis.There were 108 patients in our study. They were randomly assigned to 2 groups. In group A, patients received Weierkang pills and patients in group B received folic acid combined with teprenone. Symptoms, endoscopic scores, and biopsy specimens were compared at baseline and 3 months after treatment. Meanwhile, the expressions of vascular endothelial growth factor and trefoil factor 3 (TFF3) in biopsy specimens were also compared.Our study showed that the total effective rates of atrophy/intestinal metaplasia in group A reached the same level as group B (51.7% vs. 40.0%, P =0.419). Weierkang significantly improved the total effective rate of atrophy/intestinal metaplasia in gastric angle compared with group B (64.7% vs. 33.3%, P =0.024). Weierkang can significantly lower the total Kyoto risk score (2.6±1.1 vs. 3.3±1.0, P =0.002) and atrophy score (1.4±0.6 vs. 1.8±0.5, P =0.001) after treatment. In addition, Weierkang improves symptoms (1.3±1.3 vs. 2.3±1.8, P =0.003) and epigastric pain (0.2±0.4 vs. 0.5±0.6, P =0.041). The expression of TFF3 in gastric mucosa decreased significantly after treatment with Weierkang ( P =0.002).Weierkang can improve the endoscopic appearance and pathologic changes of chronic atrophic gastritis patients. Symptoms also improved. TFF3 may be involved the pathophysiology mechanism. 

Santiago Iñiguez

Papers

Interpenetrating structure for efficient Sb2Se3 nanorod array solar cells loaded with CuInSe2 QDs sensitizer

Interpenetrating structure for efficient Sb2Se3 nanorod array solar cells loaded with CuInSe2 QDs sensitizer

Combined effects of electric supercharger and LP-EGR on performance of turbocharged engine

A Randomized Double-blind Clinical Trial of Weierkang Pills for the Treatment of Chronic Atrophic Gastritis