Strong Electronic Interaction in High-Entropy Oxide Enhances Oxygen Evolution Reaction.

High-entropy oxides are a new type of material with significant application potential. However, the lack of a universal HEO preparation method severely limits the property study and application of HEOs. Herein, we report a universal approach of spray pyrolysis for the preparation of various HEOs and study the electrocatalytic performance of HEOs toward the oxygen evolution reaction. FeCoNiMoWOx HEO exhibits an overpotential of 281 mV at 10 mA cm-2 and a Tafel slope of 34.5 mV dec-1, which are far superior to those of the corresponding medium-entropy oxide and low-entropy oxide. It is found that the high entropy of the HEO greatly strengthens the interaction between Fe and Mo/W and produces abundant oxygen vacancies (OVs) around Mo and W. This work not only provides a universal preparation method for HEOs but also deepens our understanding of OER catalytic activity of HEOs.

Unveiling the Effect of Organic Sulfur Sources on Synthesized MoS2 Phases and Electrocatalytic Hydrogen Evolution Performances.

Metallic-phase MoS2 exhibits Pt-comparable electrocatalytic hydrogen evolution reaction (HER) performance in acidic conditions. However, the controllable synthesis of metallic-phase MoS2 is quite challenging because the key factor determining the phase types of MoS2 during synthesis is still unclear. Herein, the effect of organic sulfur sources on the formed MoS2 phase is studied by use of thioacetamide (TAA), l-cysteine, and thiourea as sulfur sources. The TAA and l-cysteine produce metallic MoS2, while thiourea gives rise to semiconducting MoS2. Owing to the metallic phase and smaller size, the MoS2 prepared with TAA and l-cysteine has a higher electrocatalytic HER activity than the MoS2 obtained from thiourea. The HER overpotential of MoS2 synthesized with TAA is only 210 mV for reaching the current density of 10 mA/cm2, and the corresponding Tafel slope is 44 mV/decade. Further studies find that the decomposition temperature of sulfur precursors is the key factor for the formation of metallic MoS2. Sulfur precursors with a lower decomposition temperature release sulfur ions quickly, which in turn stabilize the metallic phase and inhibit the growth of MoS2 into large sizes. Our findings unveil the key factor for controlling the phase type of MoS2 synthesized from organic sulfur precursors and will be very helpful for the synthesis of MoS2 with high electrocatalytic activity.

[Acupuncture at "seven acupoints on neck" for cervical spondylosis of vertebral artery type].

OBJECTIVE: To compare the efficacy difference among acupuncture at "seven acupoints on neck", acupuncture at regular acupoints and betahistine mesilate tablet for cervical spondylosis of vertebral artery type, and to explore the effective treatment for cervical spondylosis of vertebral artery type. METHODS: Ninety patients were randomly divided into a regular acupuncture group, a medication group and a neck-seven-acupoint group, 30 cases in each group. According to the acupoints prescription for vertigo in "11th Five-Year" Nation Textbook Acupuncture and Moxibustion, the patients in the regular acupuncture group were treated with acupuncture at Fengchi (GB 20) and Baihui (GV 20), etc.; the patients in the neck-seven-acupoint group were treated with Fengfu (GV 16), Fengchi (GB 20), Tianzhu (BL 10) and Wangu (GB 12); the two groups were treated once a day, 6 treatments were taken as one course; there was an interval of 1 day between course and totally two course were given. The patients in the medication group were treated with betahistine mesilate tablets, 1 tablet each time, 3 times a day, for 2 weeks. The vertigo symptom and function score, mean blood flow velocity of left vertebral artery (LVA), right vertebral artery (RVA), basilar artery (BA) as well as pulsatile index (PI) and resistance index (RI) were observed, and the clinical efficacy of the three groups was compared. RESULTS: The total effective rate was 93.3% (28/30) in the neck-seven-acupoint group, which was superior to 76.7% (23/30) in the regular acupuncture group and 70.0% (21/30) in the medication group (both P<0.05). The vertigo symptom and function score were all improved after treatment in the three groups (all P<0.05), and the improvement in the neck-seven-acupoint group was superior to those in the regular acupuncture group and medication group (both P<0.05). The mean blood flow velocity of LVA, RVA and BA was all improved after treatment in the neck-seven-acupoint group and regular acupuncture group (all P<0.05), which was not significant in the medication group (all P>0.05). The improvement of mean blood flow velocity in the neck-seven-acupoint group was superior to those in the medication group and regular acupuncture group (all P<0.05); the improvement in the regular acupuncture group was superior to that in the medication group (all P<0.05). PI and RI were all reduced after treatment in the three groups (all P<0.05); the reduction in the neck-seven-acupoint group was more significant those those in the medication group and regular acupuncture group (all P<0.05), and the reduction in the regular acupuncture group was superior to that in the medication group (all P<0.05). CONCLUSION: Acupuncture at "seven acupoints on neck" has better clinical efficacy than regular acupuncture and betahistine mesilate tablets, which could obviously improve vertigo and brain blood supply.