Aqueous electrolytes come with an intrinsic narrow electrochemical stability window (1.23 V). Expanding this window represents significant benefits in both fundamental science and practical battery applications. Recent breakthroughs made via super-concentration have resulted in >3.0 V windows, but fundamental understanding of the related mechanism is still absent. In the present work, we examined the widened window (2.55 V) of a super-concentrated (unsaturated) aqueous solution of LiNO 3 through both theoretical and spectral analyses and discovered that a local structure of intimate Li + -water interaction arises at super-concentration, generating (Li + (H 2 O) 2 ) n polymer-like chains to replace the ubiquitous hydrogen bonding between water molecules. Such structure is mainly responsible for the expanded electrochemical stability window. Further theoretical and experimental analyses quantitatively differentiate the contributions to this window, identifying the kinetic factor (desolvation) as the main contributor. Such molecular-level and quantitative understanding will further assist in tailor designing more effective approaches to stabilizing water electrochemically.

A flexible composite solid electrolyte membrane consisting of inorganic solid particles (Li1.3Al0.3Ti1.7(PO4)3), polyethylene oxide (PEO), and boronized polyethylene glycol (BPEG) is prepared and investigated. This membrane exhibits good stability against lithium dendrite, which can be attributed to its well‐designed combination components: the compact inorganic lithium ion conducting layer provides the membrane with good mechanical strength and physically barricades the free growth of lithium dendrite; while the addition of planar BPEG oligomers not only disorganizes the crystallinity of the PEO domain, leading to good ionic conductivity, but also facilitates a “soft contact” between interfaces, which not only chemically enables homogeneous lithium plating/stripping on the lithium metal anode, but also reduces the polarization effects. In addition, by employing this membrane to a LiFePO4/Li cell and testing its galvanostatic cycling performances at 60 °C, capacities of 158.2 and 94.2 mA h g−1 are delivered at 0.1 C and 2 C, respectively.

As a compound analogue of black phosphorus, a new 2D semiconductor of SnS layers is proposed. Based on state-of-the-art theoretical calculations, we confirm that such 2D SnS layers are thermally and dynamically stable and can be mechanically exoliated from α-phase SnS bulk materials. The 2D SnS layer has an indirect band gap that can be tuned from 1.96 eV for the monolayer to 1.44 eV for a six-layer structure. Interestingly, the decrease of the band gap with increasing number of layers is not monotonic but shows an odd−even quantum confinement effect, because the interplay of spin−orbit coupling and lack of inversion symmetry in odd-numbered layer structures results in anisotropic spin splitting of the energy bands. It was also found that such 2D SnS layers show high in-plane anisotropy and high carrier mobility (tens of thousands of cm 2 V −1 s −1 ) even superior to that of black phosphorus, which is dominated by electrons. With these intriguing electronic properties, such 2D SnS layers are expected to have great potential for application in future nanoelectronics.

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Triple cation perovskites (Cs 0.05 (MA 0.17 FA 0.83 ) 0.95 Pb(I 0.83 Br 0.17 ) 3 ) have received lots of attention owing to the excellent stability and photovoltaic performance. However, the development toward efficient solar cells has been significantly impeded by its intrinsic precursor instability, as well as defective crystal surface. Herein, a strategy for introducing the additive of 1,4,7,10,13,16-hexaoxacyclooctadecane (18C6) in the precursor solution, rendering an excellent stability of more than one month, and the defect passivation effect on the crystal surface are demonstrated. In those perovskite solar cells, a power conversion efficiency of 20.73% has been achieved with a substantially improved open-circuit voltage and fill factor. As evidenced by the density functional theory calculations, the fundamental reason relating to the enhanced performance is found to be the interaction effect between the 18C6 and cations, and in particular the formation of the 18C6/Pb complex. This finding represents an alternative strategy for achieving a stable precursor solution and efficient perovskite solar cells.

Little is known about the risk factors associated with hepatitis B virus (HBV) intrauterine transmission among HBsAg positive mothers. We conducted a study in Taiyuan, China including 1,133 HBsAg positive mothers and their babies. A total of 101 neonates had HBsAg and/or HBV DNA positive with an intrauterine transmission rate of 8.9%. Maternal menstrual irregularity (OR=4.95, 95%CI: 1.71, 14.33) and severe nausea during the first trimester (OR=1.86, 95%CI: 1.11, 3.09) were associated with an increased risk of intrauterine transmission, while cesarean delivery (OR=0.32, 95%CI: 0.20, 0.51) was associated with a decreased risk after adjusting for potential confounders. Maternal HBeAg positive was a strong independent predictor for intrauterine transmission (OR=2.56, 95%CI: 1.54, 4.27). A positive association between maternal HBV DNA levels and intrauterine transmission was suggested. Maternal HBIG administration during pregnancy, family history of HBV infection, and premature rupture of membranes were not associated with the risk of intrauterine transmission. The study confirmed that maternal HBeAg positive was a risk factor and cesarean delivery was a protective factor for intrauterine transmission. The new findings associated with menstrual irregularity and severe nausea during the first trimester warrant further investigation.

Purpose Adolescents’ and young adults’ perception of homosexuality plays an important role in the marginalization and stigmatization of the homosexual, thereby influencing his or her health. This article aims to study that perception and to examine its predictors in three Asian cities that are culturally dominated by Confucianism. Methods From May 2006 to January 2007, a cross-sectional survey of 17,016 adolescents and young adults, aged 15–24 years old, in both urban and rural sites of three Asian cities (Hanoi in Vietnam, Shanghai in the mainland of China, and Taipei in Taiwan) was conducted through interview and computer-assisted self-interview for sensitive questions. Chi-square tests and multivariate logistic regression were performed to identify the predictors for their perception of homosexuality. Results The percentage of adolescents and young adults who hold a positive view of homosexuality (i.e., thought it was normal and/or acceptable) was low, especially in Hanoi and Shanghai; these figures increased from Hanoi to Shanghai to Taipei for both males and females. Overall, those factors significantly associated with adolescents’ and young adults’ perception of homosexuality included individuals’ demographic characteristics (urban/rural, age, economic status, student status, and educational level), preferred origin of movies/videos, self-identified sexual orientation, sexual and reproductive health knowledge, family values, gender role values, and attitudes toward premarital sex. Conclusions In these three Asian cities composed of populations whose views are largely influenced by Confucianism, adolescents and young adults mainly hold a negative perception of homosexuality. The most common and important predictors for a respondent's perception of homosexuality were his or her knowledge of sexual and reproductive health and how traditional his/her values may be. Greater attention needs to be paid to the popularization of knowledge about sexual and reproductive health including homosexuality—and to efforts aimed at instilling more liberal attitudes to improve adolescents’ and young adults’ perception of homosexuality. This could then reduce the marginalization and stigmatization of the homosexual, and thus improve his/her health.

Poly (3-hexylthiophene) (P3HT) is one of the most attractive hole transport materials (HTMs) for the pursuit of stable, low-cost, and high-efficiency perovskite solar cells (PSCs). However, the poor contact and the severe recombination at P3HT/perovskite interface lead to a low power conversion efficiency (PCE). Thus, we construct a molecular bridge, 2-((7-(4-(bis(4-methoxyphenyl)amino)phenyl)−10-(2-(2-ethoxyethoxy)ethyl)−10H-phenoxazin-3-yl)methylene)malononitrile (MDN), whose malononitrile group can anchor the perovskite surface while the triphenylamine group can form π−π stacking with P3HT, to form a charge transport channel. In addition, MDN is also found effectively passivate the defects and reduce the recombination to a large extent. Finally, a PCE of 22.87% has been achieved with MDN-doped P3HT (M-P3HT) as HTM, much higher than the efficiency of PSCs with pristine P3HT. Furthermore, MDN gives the un-encapsulated device enhanced long-term stability that 92% of its initial efficiency maintain even after two months of aging at 75% relative humidity (RH) follow by one month of aging at 85% RH in the atmosphere, and the PCE does not change after operating at the maximum power point (MPP) under 1 sun illumination (~45 oC in N2) over 500 hours.