Photoreduction of CO 2 provides an appealing way to alleviate the energy crisis and manage the global carbon balance but is limited by the high activation energy and the rate-limiting proton transfer. We now develop a...
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Photoreduction of CO 2 provides an appealing way to alleviate the energy crisis and manage the global carbon balance but is limited by the high activation energy and the rate-limiting proton transfer. We now develop a dual-site strategy for high-efficiency CO 2 conversion through polarizing CO 2 molecules at pyridine N vacancies and accelerating the intermediate protonation by protonated pyridine N adjacent to nitrogen vacancies on polymeric carbon nitride. Our photocatalysts with atomic-level engineered active sites manifest a high CO production rate of 1835 μmol g −1 h −1 , 183 times higher than the pristine bulk carbon nitride. Theoretical prediction and experimental studies confirm that such excellent performance is attributed to the synergistic effect between vacant and protonated pyridine N in decreasing the formation energy of the key *COOH intermediates and the efficient electron transfer relay facilitated by the defect-induced shallow trap state and homogeneous charge mediators.
The construction of Sponge City (SPC) in China has caused a huge social transformation, and the application of its core low-impact development facilities (LIDs) has changed the lives of residents from the details. Con...
The construction of Sponge City (SPC) in China has caused a huge social transformation, and the application of its core low-impact development facilities (LIDs) has changed the lives of residents from the details. controlling runoff water quantity and its water quality are the two main objectives of low impact development measures. This paper discusses the results of water quality testing, comparing content changes of total phosphorus (TP), total nitrogen (TN), and chemical oxygen demand (COD) and total suspended solids (TSS) measured from water samples collected from the same LID facilities established by LCTIP three times a month during 2018 the local rainy season. The values changes of various pollutants from sampling points to the outlet show that the water quality of after LID facilities is close to the state of natural rain before development. The water purification effect of the LID facility was verified. At the same time, it is necessary to understand that more factors will have an impact on water quality. Therefore, the limitations of current knowledge and recommendations for future research are also discussed.
Probing interactions of biological systems at the molecular level is of great importance to fundamental biology, diagnosis, and drug discovery. A rational bioassay design of lithographically integrating individual poi...
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Probing interactions of biological systems at the molecular level is of great importance to fundamental biology, diagnosis, and drug discovery. A rational bioassay design of lithographically integrating individual point scattering sites into electrical circuits is capable of realizing real‐time, label‐free biodetection of influenza H1N1 viruses with single‐molecule sensitivity and high selectivity by using silicon nanowires as local reporters in combination with microfluidics. This nanocircuit‐based architecture is complementary to more conventional optical techniques, but has the advantages of no bleaching problems and no fluorescent labeling. These advantages offer a promising platform for exploring dynamics of stochastic processes in biological systems and gaining information from genomics to proteomics to improve accurate molecular and even point‐of‐care clinical diagnosis.
Heavy metals, notably Pb2+and Cu2+, are some of the most persistent contaminants found in groundwater. Frequent monitoring of these metals, which relies on efficient, sensitive, cost-effective, and reliable methods, i...
Heavy metals, notably Pb2+and Cu2+, are some of the most persistent contaminants found in groundwater. Frequent monitoring of these metals, which relies on efficient, sensitive, cost-effective, and reliable methods, is a necessity. We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu2+by exploiting the electroanalytical technique of square wave *** also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam, which is then electrochemically seeded with gold nanoparticles（Au NPs）. The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O. As a result, the heavy metals Pb2+(0.020 mg.L-1detection limit; 2.0–16.0 mg.L-1detection range)and Cu2+(0.013 mg.L-1detection limit; 0.4–12.8 mg.L-1detection range) can be detected simultaneously with high precision. Furthermore, other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode's performance, and the recovery rate of groundwater samples varied between 96.3% ± 2.1% and 109.4% ± 0.6%. The compactness, flexible shape, low power consumption, and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater, thereby demonstrating the potential to revolutionize the field of environmental monitoring.
Changes in CO2 emissions during the COVID-19 pandemic have been estimated from indicators on activities like transportation and electricity generation. Here, we instead use satellite observations together with bottom-...
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Atomically dispersed metal-nitrogen sites show great prospect for the oxygen reduction reaction (ORR), whereas the unsatisfactory adsorption-desorption behaviors of oxygenated intermediates on the metal centers impede...
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Atomically dispersed metal-nitrogen sites show great prospect for the oxygen reduction reaction (ORR), whereas the unsatisfactory adsorption-desorption behaviors of oxygenated intermediates on the metal centers impede improvement of the ORR performance. We propose a new conceptual strategy of introducing sacrificial bonds to remold the local coordination of Fe−N x sites, via controlling the dynamic transformation of the Fe−S bonds in the Fe−N−C single-atom catalyst. Spectroscopic and theoretical results reveal that the selective cleavage of the sacrificial Fe−S bonds induces the incorporation of the electron-withdrawing oxidized sulfur on the Fe centers. The newly functionalized moieties endow the catalyst with superior ORR activity and remarkable stability, owing to the reduced electron localization around the Fe centers facilitating the desorption of ORR intermediates. These findings provide a unique perspective for precisely controlling the coordination structure of single-atom materials to optimize their activity.
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