Achieving a functional and durable non-platinum group metal-based methanol oxidation catalyst is critical for a cost-effective direct methanol fuel cell. While Ni(OH)2 has been widely studied as methanol oxidation catalyst, the initial process of oxidizing Ni(OH)2 to NiOOH requires a high potential of 1.35 V vs. RHE. Such potential would be impractical since the theoretical potential of the cathodic oxygen reduction reaction is at 1.23 V. Here we show that a four-coordinated nickel atom is able to form charge-transfer orbitals through delocalization of electrons near the Fermi energy level. As such, our previously reported periodically arranged four-six-coordinated nickel hydroxide nanoribbon structure (NR-Ni(OH)2) is able to show remarkable methanol oxidation activity with an onset potential of 0.55 V vs. RHE and suggests the operability in direct methanol fuel cell configuration. Thus, this strategy offers a gateway towards the development of high performance and durable non-platinum direct methanol fuel cell.

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BackgroundUp to now, numerous case-control studies have reported the associations between fat mass and obesity associated (FTO) gene rs9939609 A/T polymorphism and polycystic ovary syndrome (PCOS), however, without a consistent result. Hence we performed current systematic review and meta-analysis to clarify the controversial results.MethodsCase-control studies reporting the relationship of rs9939609 A/T polymorphism and PCOS published before April 2015 were searched in Pubmed database without language restriction. Data was analyzed by Review Manager 5.2.ResultsA total of five studies involving 5010 PCOS patients and 5300 controls were included for further meta-analysis. The results of meta-analysis showed that the FTO gene rs9939609 A/T polymorphism was significantly different between PCOS group and control group in different gene models (For AA + AT vs. TT: OR = 1.41, 95% CI = 1.28–1.55, P < 0.00001. For AA vs. AT + TT: OR = 1.54, 95% CI = 1.25–1.89, P < 0.0001. For AA vs. TT: OR = 1.74, 95% CI = 1.38–2.18, P < 0.00001. For A vs. T: OR = 1.36, 95% CI = 1.25–1.47, P < 0.00001, respectively) suggesting that A allele was a risk factor for PCOS susceptibility. Furthermore, subgroup analysis in Asian and Caucasian ethnicities also found significant association between rs9939609 A/T polymorphism and PCOS (In Asian subgroup: OR = 1.43, 95% CI = 1.29–1.59, P < 0.0001. In Caucasian subgroup: OR = 1.33, 95% CI = 1.08–1.64, P = 0.008)ConclusionThis meta-analysis suggests that rs9939609 A/T polymorphism of FTO gene is associated with PCOS risk, and that A allele is a risk factor for PCOS susceptibility simultaneously.

With the rapid development of wearable and intelligent flexible electronic devices (FEDs), the demand for flexible energy storage/conversion devices (ESCDs) has also increased. Rechargeable flexible metal‐air batteries (MABs) are expected to be one of the most ideal ESCDs due to their high theoretical energy density, cost advantage, and strong deformation adaptability. With the improvement of the device design, material assemblies, and manufacturing technology, the research on the electrochemical performance of flexible MABs has made significant progress. However, achieving the high mechanical flexibility, high safety, and wearable comfortability required by FEDs while maintaining the high performance of flexible MABs are still a daunting challenge. In this review, flexible Zn‐air and Li‐air batteries are mainly exemplified to describe the most recent progress and challenges of flexible MABs. We start with an overview of the structure and configuration of the flexible MABs and discuss their impact on battery performance and function. Then it focuses on the research progress of flexible metal anodes, gel polymer electrolytes, and air cathodes. Finally, the main challenges and future research perspectives involving flexible MABs for FEDs are proposed.

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