2 research outputs found
H:ZnO Nanorod-Based Photoanode Sensitized by CdS and Carbon Quantum Dots for Photoelectrochemical Water Splitting
We report a promising simple strategy
for improving the performance
of the photoanode for photoelectrochemical (PEC) water splitting.
ZnO nanorods on an indium tin oxide glass substrate were synthesized
by a hydrothermal method following calcinations in air at 500 °C
for 2 h and pure ambient hydrogen at atmospheric pressure at 400 °C
for 30 min. The hydrogenated ZnO (H:ZnO) sample shows an enhanced
photocurrent in comparison to that of ZnO nanorods. To enhance the
absorption in the visible light and near-infrared regions, H:ZnO nanorods
were sensitized by cadmium sulfide (CdS) nanoparticles and carbon
quantum dots (CQDs). The H:ZnO nanorod film sensitized in this way
exhibited significantly improved PEC properties after treatment with
ambient nitrogen at 400 °C for 30 min. The optimized H:ZnO nanorod
sample sensitized by CdS and CQDs yields a photocurrent density of
∼12.82 mA/cm<sup>2</sup> at 0 V (vs saturated calomel electrode
(SCE)) in 0.25 M Na<sub>2</sub>S and 0.35 M Na<sub>2</sub>SO<sub>3</sub> solution under the illumination of simulated solar light (100 mW/cm<sup>2</sup> from a 150 W xenon Arc lamp source). The optimal structure
shows a solar-to-hydrogen conversion efficiency of ∼3.85% (at
−0.67 V vs SCE). The H<sub>2</sub> gas generation obtained
using this optimal structure consisting of H:ZnO nanorods sensitized
by CdS and CQDs was 7.04 mL/cm<sup>2</sup> in 1 h. The morphology
and properties of the samples were examined by scanning electron microscopy,
X-ray diffraction, transmission electron microscopy, ultraviolet–visible
absorption, and electrical measurements
Table1_Unravelling the determinants of human health in French Polynesia: the MATAEA project.docx
BackgroundFrench Polynesia is a French overseas collectivity in the Southeast Pacific, comprising 75 inhabited islands across five archipelagoes. The human settlement of the region corresponds to the last massive migration of humans to empty territories, but its timeline is still debated. Despite their recent population history and geographical isolation, inhabitants of French Polynesia experience health issues similar to those of continental countries. Modern lifestyles and increased longevity have led to a rise in non-communicable diseases (NCDs) such as obesity, diabetes, hypertension, and cardiovascular diseases. Likewise, international trade and people mobility have caused the emergence of communicable diseases (CDs) including mosquito-borne and respiratory diseases. Additionally, chronic pathologies including acute rheumatic fever, liver diseases, and ciguatera, are highly prevalent in French Polynesia. However, data on such diseases are scarce and not representative of the geographic fragmentation of the population.ObjectivesThe present project aims to estimate the prevalence of several NCDs and CDs in the population of the five archipelagoes, and identify associated risk factors. Moreover, genetic analyses will contribute to determine the sequence and timings of the peopling history of French Polynesia, and identify causal links between past genetic adaptation to island environments, and present-day susceptibility to certain diseases.MethodsThis cross-sectional survey is based on the random selection of 2,100 adults aged 18–69 years and residing on 18 islands from the five archipelagoes. Each participant answered a questionnaire on a wide range of topics (including demographic characteristics, lifestyle habits and medical history), underwent physical measurements (height, weight, waist circumference, arterial pressure, and skin pigmentation), and provided biological samples (blood, saliva, and stool) for biological, genetic and microbiological analyses.ConclusionFor the first time in French Polynesia, the present project allows to collect a wide range of data to explore the existence of indicators and/or risk factors for multiple pathologies of public health concern. The results will help health authorities to adapt actions and preventive measures aimed at reducing the incidence of NCDs and CDs. Moreover, the new genomic data generated in this study, combined with anthropological data, will increase our understanding of the peopling history of French Polynesia.Clinical trial registrationhttps://clinicaltrials.gov/, identifier: NCT06133400.</p