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Understanding the fundamental properties of buried interfaces in perovskite photovoltaics is of paramount importance to the enhancement of device efficiency and stability. Nevertheless, accessing buried interfaces poses a sizeable challenge because of their non-exposed feature. Herein, the mystery of the buried interface in full device stacks is deciphered by combining advanced in situ spectroscopy techniques with a facile lift-off strategy. By establishing the microstructure-property relations, the basic losses at the contact interfaces are systematically presented, and it is found that the buried interface losses induced by both the sub-microscale extended imperfections and lead-halide inhomogeneities are major roadblocks toward improvement of device performance. The losses can be considerably mitigated by the use of a passivation-molecule-assisted microstructural reconstruction, which unlocks the full potential for improving device performance. The findings open a new avenue to understanding performance losses and thus the design of new passivation strategies to remove imperfections at the top surfaces and buried interfaces of perovskite photovoltaics, resulting in substantial enhancement in device performance.

P2-type Na2/3Ni1/3Mn2/3O2 is an air-stable cathode material for sodium-ion batteries. However, it suffers irreversible P2-O2 phase transition in 4.2-V plateau and shows poor cycling stability and rate capability within this plateau. To evaluate the practicability of this material in 2.3–4.1 V voltage range, single-crystal micro-sized P2-type Na2/3Ni1/3Mn2/3O2 with high rate capability and cycling stability is synthesized via polyvinylpyrrolidone (PVP)-combustion method. The electrochemical performance is evaluated by galvanostatic charge-discharge tests. The kinetics of Na+ intercalation/deintercalation is studied detailly with potential intermittent titration technique (PITT), galvanostatic intermittent titration technique (GITT) and cyclic voltammetry (CV). The discharge capacity at 0.1 C in 2.3–4.1 V is 87.6 mAh g−1. It can deliver 91.5% capacity at 40 C rate and keep 89% after 650 cycles at 5C. The calculated theoretical energy density of full cell with hard carbon anode is 210 Wh kg−1. The moderate energy density associated with high power density and long cycle life is acceptable for load adjustment of new-energy power, showing the prospect of practical application.

Recently, halide solid state electrolytes (SSEs) have received great attention owing to their fast ionic conductivity, high oxidation potential, and good chemical and electrochemical compatibility with high voltage cathode materials. However, most of reported halide SSEs contain rather rare and expensive elements, which hinders their sustainable utilizations in practical batteries. Here in this work, under the guidance of systematic modelling based on the density functional theory (DFT), a low‐cost alternative is developed through optimizing the lattice chemistry in a recently identified spinel‐like chloride Li2CrCl4 into Li5/3Cr1/3Zr1/3Cl4 for remarkably enhanced ionic conductivity and stable electrochemical window with respect to the Li‐anode. This new phase has then been synthesized successfully, delivering an ionic conductivity over 1200 times of that of the pristine phase Li2CrCl4, in addition to a high oxidation potential (up to 4.1 V vs Li/Li+) to enable outstanding interfacial compatibility with high voltage cathodes. Such a high‐voltage and fast Li‐ion conducting solid‐state electrolyte is expected to provide a highly desirable basis toward developing high energy‐density all solid‐state batteries (ASSBs) using economical and Earth‐rich elements. [ABSTRACT FROM AUTHOR]

Different cadmium (Cd)-accumulated rice genotypes (Erjiunan 1 and Fupin 36) were used to explore the effect of rice rhizosphere aeration on Cd uptake and accumulation. Aeration in the nutrient solution influenced the agronomic characteristics induced by Cd-stress, such as the increases of rice root length and root vigor, but the reductions of plant height and shoot dry weight. Aeration also alleviated the decreasing effects of Cd stress on antioxidant enzyme activities and soluble protein, malonaldehyde and nicotianamine contents in rice. Moreover, with aeration treatment, the accumulation and bioavailability of metal elements changed significantly, with a Cd increase and an Fe reduction in both rice genotypes. In addition, at the molecular level, aeration upregulated the expression of Fe-inducible genes (such as OsIRT1, OsNRAMP1, OsYSL15 and OsNAS3). Furthermore, as a Cd2+/Fe2+ transporter, the high transcription level of OsNRAMP1 can elevate the Cd uptake and translocation in rice due to the Fe reduction caused by aeration and Cd-exposure, which indicated that OsNRAMP1 might play a crucial role in the effect of aeration on Cd uptake and accumulation.