Construction of Z-scheme heterostructure is of great significance for realizing efficient photocatalytic water splitting. However, the conscious modulation of Z-scheme charge transfer is still a great challenge. Herein, interfacial Mo-S bond and internal electric field modulated Z-scheme heterostructure composed by sulfur vacancies-rich ZnIn2S4 and MoSe2 was rationally fabricated for efficient photocatalytic hydrogen evolution. Systematic investigations reveal that Mo-S bond and internal electric field induce the Z-scheme charge transfer mechanism as confirmed by the surface photovoltage spectra, DMPO spin-trapping electron paramagnetic resonance spectra and density functional theory calculations. Under the intense synergy among the Mo-S bond, internal electric field and S-vacancies, the optimized photocatalyst exhibits high hydrogen evolution rate of 63.21 mmol∙g−1·h−1 with an apparent quantum yield of 76.48% at 420 nm monochromatic light, which is about 18.8-fold of the pristine ZIS. This work affords a useful inspiration on consciously modulating Z-scheme charge transfer by atomic-level interface control and internal electric field to signally promote the photocatalytic performance.

Designing electrocatalysts with high-performance for both reduction and oxidation reactions faces severe challenges. Here, the uniform and ultrasmall (~3.4 nm) high-entropy alloys (HEAs) Pt18Ni26Fe15Co14Cu27 nanoparticles are synthesized by a simple low-temperature oil phase strategy at atmospheric pressure. The Pt18Ni26Fe15Co14Cu27/C catalyst exhibits excellent electrocatalytic performance for hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR). The catalyst shows ultrasmall overpotential of 11 mV at the current density of 10 mA cm−2, excellent activity (10.96 A mg−1Pt at −0.07 V vs. reversible hydrogen electrode) and stability in the alkaline medium. Furthermore, it is also the efficient catalyst (15.04 A mg−1Pt) ever reported for MOR in alkaline solution. Periodic DFT calculations confirm the multi-active sites for both HER and MOR on the HEA surface as the key factor for both proton and intermediate transformation. Meanwhile, the construction of HEA surfaces supplies the fast site-to-site electron transfer for both reduction and oxidation processes.

Objective: We aimed to investigate the relationship between clinical characteristics, outcomes and the severity of severe acute respiratory syndrome coronavirus 2 pneumonia. Methods: We performed a systematic review and meta-analysis using PubMed, Embase, and Cochrane Library databases to assess the clinical characteristics and outcomes of confirmed COVID-19 cases and compared severe (ICU) and nonsevere (non-ICU) groups. Results: We included 12 cohort studies including 2,445 patients with COVID-19. Compared with nonsevere (non-ICU) patients, severe (ICU) disease was associated with a smoking history (P = .003) and comorbidities including chronic obstructive pulmonary disease (OR = 5.08, P < .001), diabetes (OR = 3.17, P < .001), hypertension (OR = 2.40, P < .001), coronary heart disease (OR = 2.66, P < .001), cerebrovascular diseases (OR = 2.68, P = .008), and malignancy (OR=2.21, P = .040). We found significant differences between the 2 groups for fever, dyspnea, decreased lymphocyte and platelet counts, and increased leukocyte count, C-creative protein, procalcitonin, lactose dehydrogenase, aspartate aminotransferase, alanine aminotransferase, creatinine kinase, and creatinine levels (P < .05). Significant differences were also observed for multiple treatments (P < .05). Patients in the severe (ICU) group were more likely to have complications and had a much higher mortality rate and lower discharge rate than those with nonsevere (non-ICU) disease (P < .05). Conclusions: Investigation of clinical characteristics and outcomes of severe cases of COVID-19 will contribute to early prediction, accurate diagnosis, and treatment to improve the prognosis of patients with severe illness.

Exploring a simple, fast, solvent-free synthetic method for large-scale preparation of cheap, highly active electrocatalysts for industrial hydrogen evolution reaction is one of the most promising work today. In this work, a simple, fast and solvent-free microwave pyrolysis method is used to synthesize ultra-small (3.5 nm) Ru-Mo2C@CNT catalyst with heterogeneous structure and strong metal-support interaction in one step. The Ru-Mo2C@CNT catalyst only exhibits an overpotential of 15 mV at a current density of 10 mA cm−2, and exhibits a large turnover frequency value up to 21.9 s−1 under an overpotential of 100 mV in 1.0 M KOH. In addition, this catalyst can reach high current densities of 500 mA cm−2 and 1000 mA cm−2 at low overpotentials of 56 mV and 78 mV respectively, and it displays high stability of 1000 h. This work provides a feasible way for the reasonable design of other large-scale production catalysts.

Electrocatalytic nitrogen reduction reaction (NRR) has been an important area for many scientists. However, high voltage requirements, low NH3 yield, and poor stability remain the biggest challenges for NRR. Here, novel high‐entropy alloys RuFeCoNiCu nanoparticles with small size (≈16 nm) and uniformity, prepared in oil phase at atmospheric pressure and low temperature (≤250 °C) are reported for the first time and are applied to NRR. According to the experiments, there is a high NH3 yield at a low overpotential. It has a surprising NH3 yield of 57.1 µg h–1 mgcat−1 (11.4 µg h–1 cm–2) at 0.05 V versus RHE in 0.1 m KOH, and the corresponding Faradaic efficiency reaches 38.5%, which is the electrocatalyst with the highest NH3 yield at the voltage of 0.05 V versus RHE reported so far. Similarly, the material also exhibits excellent electrochemical properties in other electrolytes such as 0.1 m Li2SO4, 0.1 m Na2SO4, and 0.1 m HCl electrolytes. Besides, after the 100 h test, only slightly diminished in activity. Theoretical calculation shows that Fe surrounded by alloy metals is the best site for N2 adsorption and activation. Co‐Cu and Ni‐Ru couples show an excellent capacity to surface hydrogenation at a low overpotential.

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Although intensive efforts have been made and great progress has been achieved relating to the electrocatalytic hydrogen evolution reaction (HER), an advanced synthesis strategy for an efficient electrocatalyst is still the most significant goal.

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