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This Tutorial teaches the essential development of nitrogen-plasma-assisted molecular-beam-epitaxy grown InGaN nanowires as an application-inspired platform for energy harvesting and conversion applications by growing dislocation- and strain-relieved axial InGaN-based nanowires. The Tutorial aims to shed light on the interfacial, surface, electrical, and photoelectrochemical characteristics of InGaN nanowires through nanoscale and ultrafast characterizations. Understanding the interrelated optical-physical properties proved critical in the development of renewable-energy harvesting and energy conversion devices. Benefiting from their unique aspect ratio and surface-to-volume ratio, semiconductor properties, and piezoelectric properties, the group-III-nitride nanowires, especially InGaN nanowires, are promising for clean energy conversion applications, including piezotronic/piezo-phototronic and solar-to-clean-fuel energy-conversion. [ABSTRACT FROM AUTHOR]

Background: Previous studies have suggested that maternal overweight/obesity is asscociated with macrosomia. The present study aimed to investigate the mediation effects of fasting plasma glucose (FPG) and maternal triglyceride (mTG) in the relationship between maternal overweight/obesity and large for gestational age (LGA) among non-diabetes pregnant women. Methods: This prospective cohort study was conducted in Shenzhen from 2017 to 2021. A total of 19,104 singleton term non-diabetic pregnancies were enrolled form a birth cohort study. FPG and mTG were measured at 24–28 weeks. We analyzed the association of maternal prepregancy overweight/obesity with LGA and mediation effects of FPG and mTG. Multivariable logistic regression analysis and serial multiple mediation analysis were performed. The odds ratio (OR) and 95% confidence intervals (CIs) were calculated. Results: Mothers who were overweight or obese had higher odds of giving birth to LGA after adjusting potential confounders (OR:1.88, 95%CI: 1.60–2.21; OR:2.72, 95%CI: 1.93–3.84, respectively). The serial multiple mediation analysis found prepregnancy overweight can not only have a direct positive effect on LGA (effect = 0.043, 95% CI: 0.028–0.058), but also have an indirect effect on the LGA through two paths: the independent mediating role of FPG (effect = 0.004, 95% CI: 0.002–0.005); the independent mediating role of mTG (effect = 0.003,95% CI: 0.002–0.005). The chain mediating role of FPG and mTG has no indirect effect. The estimated proportions mediated by FPG and mTG were 7.8% and 5.9%. Besides, the prepregnancy obesity also has a direct effect on LGA (effect = 0.076; 95%CI: 0.037–0.118) and an indirect effect on LGA through three paths: the independent mediating role of FPG (effect = 0.006; 95%CI: 0.004–0.009); the independent mediating role of mTG (effect = 0.006; 95%CI: 0.003–0.008), and the chain mediating role of FPG and mTG (effect = 0.001; 95%CI: 0.000-0.001). The estimated proportions were 6.7%, 6.7%, and 1.1%, respectively. Conclusion: This study found that in nondiabetic women, maternal overweight/obesity was associated with the occurence of LGA, and this positive association was partly mediated by FPG and mTG, suggesting that FPG and mTG in overweight/obese nondiabetic mothers deserve the attention of clinicians. [ABSTRACT FROM AUTHOR]

InGaN-based nanowires (NWs) have been extensively studied for photoelectrochemical (PEC) water splitting devices owing to their tunable bandgap and good chemical stability. Here, we further investigated the influence of Si doping on the PEC performance of InGaN-based NW photoanodes. The Si dopant concentration was controlled by tuning the Si effusion cell temperature (TSi) during plasma-assisted molecular beam epitaxy growth and further estimated by Mott-Schottky electrochemical measurements. The highest Si dopant concentration of 2.1 × 1018 cm−3 was achieved at TSi = 1120 °C, and the concentration decreased with further increases in TSi. The flat-band potential was calculated and used to estimate the conduction and valence band edge potentials of the Si-doped InGaN-based NWs. The band edge potentials were found to seamlessly straddle the redox potentials of water splitting. The linear scan voltammetry results were consistent with the estimated carrier concentration. The InGaN-based NWs doped with Si at TSi = 1120 °C exhibited almost 9 times higher current density than that of the undoped sample and a stoichiometric evolution of hydrogen and oxygen gases. Our systematic findings suggest that the PEC performance can be significantly improved by optimizing the Si doping level of InGaN-based NW photoanodes. [ABSTRACT FROM AUTHOR]

The realization of semiconductor heterostructures marks a significant advancement beyond silicon technology, driving progress in high-performance optoelectronics and photonics, including high-brightness light emitters, optical communication, and quantum technologies. In less than a decade since 1997, nanowires research has expanded into new application-driven areas, highlighting a significant shift toward more challenging and exploratory research avenues. It is therefore essential to reflect on the past motivations for nanowires development, and explore the new opportunities it can enable. The advancement of heterogeneous integration using dissimilar substrates, materials, and nanowires-semiconductor/electrolyte operating platforms is ushering in new research frontiers, including the development of perovskite-embedded solar cells, photoelectrochemical (PEC) analog and digital photonic systems, such as PEC-based photodetectors and logic circuits, as well as quantum elements, such as single-photon emitters and detectors. This review offers rejuvenating perspectives on the progress of these group-III nitride nanowires, aiming to highlight the continuity of research toward high impact, use-inspired research directions in photonics and optoelectronics., (© 2024 Wiley‐VCH GmbH.)