A p-n-p Configuration Based on the Cuprous Oxide/Silicon Tandem Photocathode for Accelerating Solar-Driven Hydrogen Evolution.

Photoelectrochemical splitting of water into hydrogen is a potential route to motivate the application of solar-driven conversion to clean energy but is regularly limited by its low efficiency. The key to addressing this issue is to design a suitable photocathode configuration for high-efficiency photogenerated carrier separation and transmission to photocathode-surface reaction sites. In this work, we report a Si-Cu2O tandem photocathode featuring a p-n-p configuration for solar-driven hydrogen evolution in an alkaline solution. Driven by this built-in field, the electrons induced from Si were transferred through FeOOH, which acted as electron tunnels, to combine with the holes from Cu2O, triggering more electrons generated from Cu2O to particiate in the surface reaction. Under simulated sunlight, the optimized photocathode achieved and maintained a photocurrent density of -11 mA/cm2 at 0 VRHE in alkaline conditions for 120 min, outperforming the reported tandem cell consisting of Si and Cu2O photocathodes. Our results provide valuable insight into a feasible way to construct an optimized photocathode for efficient solar-driven H2 evolution.

Genetic characterization and whole-genome sequencing-based genetic analysis of influenza virus in Jining City during 2021-2022.

Background: The influenza virus poses a significant threat to global public health due to its high mutation rate. Continuous surveillance, development of new vaccines, and public health measures are crucial in managing and mitigating the impact of influenza outbreaks. Methods: Nasal swabs were collected from individuals with influenza-like symptoms in Jining City during 2021-2022. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect influenza A viruses, followed by isolation using MDCK cells. Additionally, nucleic acid detection was performed to identify influenza A H1N1, seasonal H3N2, B/Victoria, and B/Yamagata strains. Whole-genome sequencing was conducted on 24 influenza virus strains, and subsequent analyses included characterization, phylogenetic construction, mutation analysis, and assessment of nucleotide diversity. Results: A total of 1,543 throat swab samples were collected. The study revealed the dominance of the B/Victoria influenza virus in Jining during 2021-2022. Whole-genome sequencing showed co-prevalence of B/Victoria influenza viruses in the branches of Victoria clade 1A.3a.1 and Victoria clade 1A.3a.2, with a higher incidence observed in winter and spring. Comparative analysis demonstrated lower similarity in the HA, MP, and PB2 gene segments of the 24 sequenced influenza virus strains compared to the Northern Hemisphere vaccine strain B/Washington/02/2019. Mutations were identified in all antigenic epitopes of the HA protein at R133G, N150K, and N197D, and the 17-sequence antigenic epitopes exhibited more than 4 amino acid variation sites, resulting in antigenic drift. Moreover, one sequence had a D197N mutation in the NA protein, while seven sequences had a K338R mutation in the PA protein. Conclusion: This study highlights the predominant presence of B/Victoria influenza strain in Jining from 2021 to 2022. The analysis also identified amino acid site variations in the antigenic epitopes, contributing to antigenic drift.

Interfacial Engineering by VOx/m-TiO2 Films for Optimizing Photon-Generated Carrier to Boost Photoelectrochemical N2 Conversion to NH3.

Optimal design of the photocathode is crucial and a meaningful approach for regulating many important photoelectrochemical (PEC) reactions. Interfacial engineering is substantiated as an effective tactic for tuning the direction of the internal carrier flow in thin-film semiconductor solar devices. Yet, so far, the type of PV device architecture involving in the interfacial transport layer is less adopted in photoelectrochemical (PEC) devices. Herein, the coupled VOx/TiO2 interfacial engineering brings in the construction of an integrated p-ZnTe hetero-structured photocathode, which was composed of a PN junction constructed with p-ZnTe and CdS, VOx as the interface layer for hole transport, and m-TiO2 as the scaffold layer. Compared with the simple PN structure, the photocathodes with the assembly of interfacial engineering enable advances in the combination of apparent quantum efficiency (AQE: 0.6%) and better yield (6.23 µg h-1 cm-2) on photoelec-N2 conversion to NH3. Interfacial engineering and heterojunction construction effects synergistically optimize photoexcited carriers and the separation and transformation at the interface. This favors easier migration of holes to the back and the assembly of electrons on the surface, achieving the intensive charge separation and surface charge injection efficiency of photogenerated carriers. Our work represents a new enlightenment for building thin-film photocathode architectures to boost the effectiveness on solar-driven utilization.

The metabolite alpha-ketobutyrate extends lifespan by promoting peroxisomal function in C. elegans.

Metabolism is intimately linked to aging. There is a growing number of studies showing that endogenous metabolites may delay aging and improve healthspan. Through the analysis of existing transcriptome data, we discover a link between activation of the transsulfuration pathway and a transcriptional program involved in peroxisome function and biogenesis in long-lived glp-1(e2141ts) mutant Caenorhabditis elegans worms. Subsequently, we show that supplementation with α-ketobutyrate, an intermediate of the transsulfuration pathway, extends lifespan in wild-type worms. Alpha-ketobutyrate augments the production of NAD+ via the lactate dehydrogenase LDH-1, leading to SIR-2.1/SIRT1-mediated enhanced peroxisome function and biogenesis, along with a concomitant increase in the expression of acox-1.2/ACOX1 in the peroxisomal fatty acid ß-oxidation pathway. ACOX-1.2/ACOX1 promotes H2O2 formation, thereby resulting in activation of SKN-1/NRF2. This transcription factor in turn extends the lifespan of worms by driving expression of autophagic and lysosomal genes. Finally, we show that α-ketobutyrate also delays the cellular senescence in fibroblast cells through the SIRT1-ACOX1-H2O2-NRF2 pathway. This finding uncovers a previously unknown role for α-ketobutyrate in organismal lifespan and healthspan by coordinating the NAD+-SIRT1 signaling and peroxisomal function.

Multistep Functional Embellishment for p-ZnTe as a Cathode to Boost the Faraday Efficiency of Nitrogen Conversion.

An electrochemical N2 reduction reaction (N2RR) is a selective sustainable approach to obtain NH3 at mild conditions and has been proposed as an alternative to the full-blown Haber-Bosch process. However, achieving high yields of NH3 and high faraday efficiency (FE) at a low overpotential remains a big challenge but has high expectations for the electrocatalytic N2RR. Herein, a novel p-ZnTe cathode multistep embellished with NiOx and ZnO thin films was prepared for boosting faraday efficiency to 9.89% for N2RR at -0.2 V vs reversible hydrogen electrode (RHE), about 12 times of p-ZnTe@ZnO. All components within the NiOx@p-ZnTe/ZnO electrode work cooperatively. A N source was determined through a 15N isotopic-labeling experiment. Using steady-state photoluminescence, electrochemical impedance spectroscopy, and control experiments, a possible model of charge transformation is built. In particular, a NiOx layer has an important impact on increasing interfacial contact between a bare fluorine-doped tin oxide (FTO) glass and p-ZnTe and further reinforcing interfacial electron transfer. This work provides a practical application and a feasible strategy to develop highly efficient catalysts for N2 reduction and also affords a guideline for the fabrication of a flat electrode.

Effect of Flank Rotation on the Photovoltaic Properties of Dithieno[2,3-d:2',3'-d']benzo[1,2-b:4,5-b']dithiophene-Based Narrow Band Gap Copolymers.

Side chain engineering has been an effective approach to modulate the solution processability, optoelectronic properties and miscibility of conjugated polymers (CPs) for organic/polymeric photovoltaic cells (PVCs). As compared with the most commonly used method of introducing alkyl chains, the employment of alkyl-substituted aryl flanks would provide two-dimensional (2-D) CPs having solution processability alongside additional merits like deepened highest occupied molecular orbital (HOMO) energy levels, increased absorption coefficient and charger transporting, etc. In this paper, the triple C≡C bond was used as conjugated linker to decrease the steric hindrance between the flanks of 4,5-didecylthien-2-yl (T) and dithieno[2,3-d:2',3'-d']benzo[1,2-b:4,5-b']dithiophene (DTBDT) core. In addition, an alternating CP derived from 4,5-didecylthien-2-yl-ethynyl (TE) flanked DTBDT, and 4,9-bis(4-octylthien-2-yl) naphtho[1,2-c:5,6-c']bis[1,2,5]thiadiazole (DTNT), named as PDTBDT-TE-DTNT, was synthesized and characterized. As compared with the controlled PDTBDT-T-DTNT, which was derived from 4,5-didecylthien-2-yl flanked DTBDT and DTNT, the results for exciton dissociation probability, density functional theory (DFT), time-resolved photoluminescence (PL) measurements, etc., revealed that the lower steric hindrance between TE and DTBDT might lead to the easier rotation of the TE flanks, thus contributing to the decrease of the exciton lifetime and dissociation probability, finally suppressing the short-circuit current density (JSC), etc., of the photovoltaic devices from PDTBDT-TE-DTNT.

Artificial Photosynthesis of Alcohols by Multi-Functionalized Semiconductor Photocathodes.

Novel artificial photosynthesis systems are devised as cells of dye/Pd/NR-MOx (M=Ti, Zn)∥CoPi/W:BiVO4 that convert efficiently CO2 to alcohols. The photocathodes are aminofunctionalized, palladium-deposited, and in situ sensitized nano-TiO2 or ZnO/FTO (FTO: fluorine-doped tin oxide) electrodes that are characterized by X-ray photoelectron spectroscopy (XPS), TEM, XRD, UV/Vis spectra, and evaluated by electrochemical techniques. The cell of dye/Pd/S-TiO2 ∥CoPi/W:BiVO4 uniquely generates ethanol under irradiation of 200 mW cm-2 , reaching 0.56 % quantum efficiency (QE) at -0.56 V and 0.13 % QE without external electron supply. The cell of dye/Pd/ N-ZnO∥CoPi/W:BiVO4 produces solely methanol at a rate of 42.8 µm h-1 cm-2 at -0.56 V of a Si solar cell, which is far less than the electrochemical voltage of water splitting (1.23 V). Its QE reaches to 0.38 %, which is equal to plants. The isotopic labeling experiments confirm the carbon source and oxygen releasing. The selectivity for alcohols of multi-functionalized semiconductors is discussed.