NaCl template-assisted construction of a CoP-MoP heterostructured electrocatalyst for electrocatalytic nitrogen reduction.

The electrocatalytic nitrogen reduction reaction (NRR) to ammonia is a promising technology to store renewable energy and mitigate greenhouse gas emissions. However, it usually suffers from low ammonia yield and selectivity because of the lack of efficient electrocatalysts. Herein, we report that the construction of metal phosphide heterojunctions is an efficient strategy for NRR activity enhancement. A CoP-MoP heterojunction electrocatalyst, which is fabricated by a facile NaCl template-assisted strategy, exhibits a favorable ammonia yield rate of 77.8 µg h-1 mgcat-1 (38.9 µg h-1 cm-2) and a high faradaic efficiency of 11.16% at -0.50 V versus the reversible hydrogen electrode. The high NRR electrocatalytic activity can be attributed to the electronic coupling effects and interfacial synergistic effects of CoP and MoP at the heterojunction interface, which accelerates the electron transfer rate. Moreover, Mo doping changes the d-band centers of metal sites on the CoP surface, which is conducive to N2 adsorption and promotes N2* adsorption in the competition of occupying active sites, thus inhibiting the HER. This work manifests the high potential of phosphide electrocatalysts and opens an alternative route toward NRR electrocatalysis.

Improved photoelectrocatalytic performances over electrochemically reduced WO3: implications of oxygen vacancies.

The introduction of rich oxygen vacancies into the WO3 lattice has been achieved through a facile and environmentally friendly route of electrochemical reduction. It has been shown that the electrochemical reduction treatment significantly increases the charge separation efficiency from 37.44% to 65.44% at 0.74 V vs. NHE, and charge injection efficiency from 15.06% to 58.20% at 0.74 V vs. NHE, leading to enhanced PEC performances for synergetic 4-CP degradation and H2 evolution. Various characterization results well demonstrated that the formation of W5+ species resulting from the introduction of oxygen vacancies in the WO3 lattice raises the Fermi level closer to the energy level of oxygen vacancies. The raised Fermi level achieves the substantial electron trap effect of the oxygen vacancies and further bends upward the band at the semiconductor/electrolyte interface, both of which play dominant roles in the effective interfacial transfer and separation of the photogenerated charges for enhanced PEC performances.

Photogenerated hole traps in metal-organic-framework photocatalysts for visible-light-driven hydrogen evolution.

Efficient electron-hole separation and carrier utilization are key factors in photocatalytic systems. Here, we use a metal-organic framework (NH2-UiO-66) modified with inner platinum nanoparticles and outer cadmium sulfide (CdS) nanoparticles to construct the ternary composite Pt@NH2-UiO-66/CdS, which has a spatially separated, hierarchical structure for enhanced visible-light-driven hydrogen evolution. Relative to pure NH2-UiO-66, Pt@NH2-UiO-66, and NH2-UiO-66/CdS samples, the Pt@NH2-UiO-66/CdS composite exhibits much higher hydrogen yields with an apparent quantum efficiency of 40.3% at 400 nm irradiation and stability over the most MOF-based photocatalysts. Transient absorption measurements reveal spatial charge-separation dynamics in the composites. The catalyst's high activity and durability are attributed to charge separation following an efficient photogenerated hole-transfer band-trap pathway. This work holds promise for enhanced MOF-based photocatalysis using efficient hole-transfer routes.

Thymosin ß10 mediates the effects of microRNA-184 in the proliferation and epithelial-mesenchymal transition of BCPAP cells.

Thyroid cancer is the most common malignant tumor of the endocrine system. It has been reported that thymosin ß10 (TMSB10) serves a vital role in tumor invasion and metastasis, and further understanding the role of TMSB10 in thyroid cancer may provide new insights into the development of novel targeted drugs. Bioinformatics analysis suggested that there might exist a regulatory relationship between miR-184 and TMSB10. Therefore, the expression of microRNA (miR)-184 was investigated in the TPC-1 and BCPAP thyroid cancer cell lines and the Nthy-ori 3-1 thyroid epithelial cell line via reverse transcription-quantitative PCR. The effect of miR-184 on BCPAP cell proliferation was evaluated using MTT and colony formation assays. In addition, the expression levels of epithelial-mesenchymal transition (EMT)-associated proteins were examined via western blot analysis and immunofluorescence staining. Furthermore, the targeting association between miR-184 and TMSB10 was verified using a dual-luciferase reporter assay. Notably, miR-184 overexpression attenuated BCPAP cell proliferation, increased the expression level of the epithelial marker E-cadherin, and decreased that of the mesenchymal marker vimentin. These effects were reversed in BCPAP cells following TMSB10 overexpression. The present study revealed that TMSB10 may be considered as a key mediator in promoting papillary thyroid carcinoma (PTC) cell proliferation and EMT, which were negatively regulated by miR-184. Therefore, the findings of the present study may provide a novel potential therapeutic target for attenuating PTC cell proliferation.

Efficient Self-Driving Photoelectrocatalytic Reactor for Synergistic Water Purification and H2 Evolution.

The photoelectrocatalytic (PEC) technique has attracted much attention to getting clear energy and environmental purification. Simultaneous reactions of solar energy generation could be used to apply for practical applications to maximize the functionality of reactor systems. Herein, we crafted a self-driving photoelectrocatalytic reactor system, comprising platinum (Pt) modified p-Si nanowires (Pt/Si-NWs) as a photocathode and TiO2 nanotube arrays (TiO2-NTAs) as a photoanode for synergistic H2 evolution and water purification, respectively. Hydrogen evolution in the cathode chamber and environmental remediation in the anode chamber were achieved with the aid of appropriate bandgap illumination and self-built bias voltage. The mismatch of Fermi levels between TiO2-NTAs and Si-NWs reduced the recombination rates of photoinduced electrons and holes through the formation of Z scheme and inner electric filed. The synergistic PEC reactions exhibited much higher activities than those achieved using other systems so far. This basic principal could be applied for fabricating other PEC reactors in photoelectro conversion devices and be established as design guidelines for reactors to maximize the PEC performance.