The approach of a hydrophilic group grafted buffer layer (HGGBL) was investigated for perovskite growth to realize highly efficient inverted planar perovskite solar cells with superior reproducibility, negligible hysteresis and improved stability.

Correction for ‘20.7% highly reproducible inverted planar perovskite solar cells with enhanced fill factor and eliminated hysteresis’ by Xixia Liu et al., Energy Environ. Sci., 2019, DOI: 10.1039/c9ee00872a.

Selecting the proper material and surface treatment methods for the elements is one of the essential problems when designing water hydraulic components due to the corrosiveness and poor lubricity of water. Experimental investigation was performed to study the tribological properties of ion nitrided 2Cr13, a kind of martensitic stainless steel, sliding on carbon fiber reinforced polyetheretherketone (CFRPEEK). The influence of factors such as sliding velocity, load, and lubrication condition were studied through experiment mainly under tap water lubrication. It was found that the friction coefficients are influenced by both the pressure and the sliding velocity. In contrast, the friction coefficients between quenched 2Cr13 and CFRPEEK are much higher. Compared with water lubrication, both the wear rate and friction coefficients increase in the case of dry friction. Wear mainly occurred on the CFRPEEK. By examining the Downloaded by [North Dakota State University] at 09:26 30 March 2015 ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT 2 worn surfaces of the specimens, it was found that adhesion was the main form of wear of the PEEK composite.