Boosting Electrocatalytic Ethylene Epoxidation by Single Atom Modulation.

The electrochemical synthesis of ethylene oxide (EO) using ethylene and water under ambient conditions presents a low-carbon alternative to existing industrial production process. Yet, the electrocatalytic ethylene epoxidation route is currently hindered by largely insufficient activity, EO selectivity, and long-term stability. Here we report a single atom Ru-doped hollandite structure KIr4O8 (KIrRuO) nanowire catalyst for efficient EO production via a chloride-mediated ethylene epoxidation process. The KIrRuO catalyst exhibits an EO partial current density up to 0.7 A cm-2 and an EO yield as high as 92.0 %. The impressive electrocatalytic performance towards ethylene epoxidation is ascribed to the modulation of electronic structures of adjacent Ir sites by single Ru atoms, which stabilizes the *CH2CH2OH intermediate and facilitates the formation of active Cl2 species during the generation of 2-chloroethanol, the precursor of EO. This work provides a single atom modulation strategy for improving the reactivity of adjacent metal sites in heterogeneous electrocatalysts.

Superatomic-Charge-Density-Wave in Cluster-Assembled Au6Te12Se8 Superconductors.

Superatomic crystals are a class of hierarchical materials composed of atomically precise clusters assembled via van der Waals or covalent-like interactions. Au6Te12Se8, an all-inorganic superatomic superconductor exhibiting superatomic-charge-density-wave (S-CDW), provides the first platform to study the response of its collective quantum phenomenon to the external pressure in superatomic crystals. We reveal a competition between S-CDW and superconductivity in an ultra-narrow pressure range. Distinct from conventional CDW ordering, S-CDW shows the lowest threshold (0.1 GPa) toward external pressure that is 1-2 orders of magnitude lower than other atomic compounds. Prominently, a second superconducting phase emerges above 7.3 GPa with a threefold enhancement in the transition temperature (Tc) to 8.5 K, indicating a switch of the conduction channel from the a- to b-axis. In situ synchrotron diffractions and theoretical calculations reveal a pressure-mediated mesoscopic slip of the superatoms and a 2D-3D transition of the Fermi surface topology, which well explains the observed dimensional crossover of conductivity and re-entrant superconductivity.

Predictive power of a body shape index and traditional anthropometric indicators for cardiovascular disease: a cohort study in rural Xinjiang, China.

BACKGROUND: A body shape index (ABSI) has been proven to be related to a population's CVD incidence. However, the application of this indicator has produced different results. AIM: This study aimed to evaluate the applicability of the ABSI in predicting the incidence of CVD in rural Xinjiang, China, and compare it with waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and body mass index (BMI). SUBJECTS AND METHODS: 5375 people aged 18 years or older were included in the study. We used the Cox proportional hazard model to evaluate the relationship between WC, WHR, WHtR, BMI, and ABSI and the incidence of CVD, the area under the curve (AUC) to evaluate the predictive power of each anthropometric index for the incidence of CVD, and restricted cubic splines are used to analyse the trend relationship between anthropometric indicators and the incidence of CVD. RESULTS: After multivariate adjustment, standardised WC, WHR, WHtR, BMI, and ABSI all positively correlated with the incidence of CVD. WC had the highest HR (95% CI) value, 1.64 (1.51-1.78), and AUC (95% CI) value, 0.7743 (0.7537-0.7949). ABSI had the lowest HR (95% CI) value, 1.21(1.10-1.32), and AUC (95% CI) value, 0.7419 (0.7208-0.7630). In the sex-specific sensitivity analysis, the predictive ability of traditional anthropometric indicators for the incidence of CVD is higher than that of ABSI. CONCLUSIONS: In the rural areas of Xinjiang, the traditional anthropometric indicators of WC had better ability to predict the incidence of CVD than ABSI.

Competition of Superconductivity and Charge Density Wave in Selective Oxidized CsV_{3}Sb_{5} Thin Flakes.

The recently discovered layered kagome metals AV_{3}Sb_{5} (A=K, Rb, and Cs) with vanadium kagome networks provide a novel platform to explore correlated quantum states intertwined with topological band structures. Here we report the prominent effect of hole doping on both superconductivity and charge density wave (CDW) order, achieved by selective oxidation of exfoliated thin flakes. A superconducting dome is revealed as a function of the effective doping content. The superconducting transition temperature (T_{c}) and upper critical field in thin flakes are significantly enhanced compared with the bulk, which are accompanied by the suppression of CDW. Our detailed analyses establish the pivotal role of van Hove singularities in promoting correlated quantum orders in these kagome metals. Our experiments not only demonstrate the intriguing nature of superconducting and CDW orders, but also provide a novel route to tune the carrier concentration through both selective oxidation and electric gating. This establishes CsV_{3}Sb_{5} as a tunable 2D platform for the further exploration of topology and correlation among 3d electrons in kagome lattices.

Metabolically healthy obesity and unhealthy normal weight rural adults in Xinjiang: prevalence and the associated factors.

BACKGROUND: This study aimed to describe the prevalence of metabolically healthy obesity (MHO) and metabolically unhealthy normal weight (MUNW) rural adults in Xinjiang and to explore their influencing factors. METHODS: We selected 13,525 Uyghur, Kazakh and Han participants in Kashi, Yili and Shihezi areas in Xinjiang from 2009 to 2010. Weight status was classified according to body mass index. Metabolic phenotype was further defined based on the National Cholesterol Education Program Adult Treatment Panel III criteria. RESULTS: The prevalence of normal weight, overweight, and obesity were 51.6, 30.2, and 14.4%, respectively. The mean age of the population was 45.04 years. The prevalence of MHO was 5.5% overall and was 38.5% among obese participants. The prevalence of MUNW was 15.5% overall and was 30.1% among normal weight participants. A metabolically healthy phenotype among obese individuals was positively associated with females and vegetable consumption ≥4 plates per week. However, this was inversely associated with higher age, red meat consumption ≥2 kg per week, and larger waist circumference (WC). Conversely, a metabolically unhealthy phenotype among normal-weight individuals was positively associated with higher age, red meat consumption ≥2 kg per week, and larger WC; this was however inversely associated with vegetable consumption ≥4 plates per week. CONCLUSIONS: The prevalence of MHO among obese adults in Xinjiang is higher than that of Han adults, while the prevalence of MUNW among normal weight adults is lower than that among Han adults. In obese and normal weight participants, higher age, more red meat consumption, and larger WC increase the risk of metabolic abnormality, and more vegetable consumption reduces the risk of metabolic abnormality.

The Association of Metabolic Syndrome with the development of cardiovascular disease among Kazakhs in remote rural areas of Xinjiang, China: a cohort study.

BACKGROUND: Metabolic syndrome (MS) can promote the development of cardiovascular disease (CVD). The objective of this study was to examine the association of MS and its components with CVD, to further prevent and control CVD in Kazakhs. METHODS: In the cohort study, a total of 2644 participants completed the baseline survey between April 2010 and December 2012.The follow-up survey was conducted from April 2016 to December 2016 and was completed by 2286 participants (86.46% follow-up rate). Cox regression was used to evaluate the association of each component and the number of combinations of MS components on the development of CVD. RESULTS: A total of 278 CVD patients were enrolled from rural residents of Xinjiang. The average age of the MS and non-MS groups was 46.33 and 38.71 years, respectively. Independent associations with CVD were found for elevated blood pressure (BP) (adjusted hazard ratio (HR) [aHR] = 1.50,95%confidence interval [CI]: 1.08-2.08), elevated waist circumference (WC) (aHR = 1.60, 95%CI: 1.19-2.15), and elevated triglycerides (TG) (aHR = 1.44, 95%CI: 1.04-2.01). Participants with one to 5 MS components had an increased HR for developing CVD, from 1.82to 8.59 (P for trend < 0.001), compared with those with no MS components. The risk of developing CVD increased when TG and WC coexisted (aHR = 2.16, 95%CI: 1.54-3.04)), when TG and BP coexisted ((aHR = 1.92, 95%CI: 1.32-2.79), and when WC and BP coexisted (aHR = 1.93, 95%CI: 1.33-2.82)). However, no significant interactions were found between BP, WC, and TG. CONCLUSIONS: Elevations of BP, WC, and TG were independent risk factors for CVD in Kazakhs. Control of these factors is important to prevent CVD in this population.

Association of total bilirubin and indirect bilirubin content with metabolic syndrome among Kazakhs in Xinjiang.

BACKGROUND: Some studies have shown that a high level of bilirubin is a protective factor against metabolic syndrome (MS), while a high level of transaminase is a risk factor for MS. However, the existing results are inconsistent and few cohort studies have been published. METHODS: Using an ambispective cohort study, 565 Kazakhs from Xinjiang, China were selected as the study subjects. The baseline serum bilirubin and transaminase levels of the subjects were divided into quartiles and the relationship between these values and the incidence of MS was analyzed. The definition of MS was based on the Joint Interim Statement (JIS) diagnostic criteria. RESULTS: The average follow-up time for the subjects was 5.72 years. The cumulative incidence of MS was 36.11% (204 of the 565 subjects), and the incidence density was 63.10/1000 person-years. Multivariate Cox regression analysis showed that the levels of total bilirubin (TBIL) and indirect bilirubin (IBIL) were negatively correlated with the occurrence of MS, Compared to the lowest quartile level (Q1), the hazard ratios of MS the TBIL levels at the Q2-Q4 quartiles were: 0.47 (0.31-0.71), 0.53 (0.35-0.79), and 0.48 (0.32-0.72), respectively, while IBIL levels at the Q2-Q4 quartiles showed an MS hazard ratio of 0.48 (0.32-0.72), 0.54(0.36-0.81), and 0.52 (0.35-0.77), respectively, all at a 95% confidence level. However, no relationship was found between transaminase levels and the incidence of MS. CONCLUSION: Serum TBIL and IBIL levels were negatively correlated with the incidence of MS in a Kazakh population in China.

Effect of metabolic syndrome on coronary heart disease in rural minorities of Xinjiang: a retrospective cohort study.

BACKGROUND: Metabolic syndrome is diagnosed by a cluster of risk factors that associated with an increased risk of coronary heart disease (CHD). We aimed to explore the impact of and interactions between individual metabolic syndrome components on the risk of CHD in Xinjiang. METHODS: The baseline population included 7635 participants. The degree to which the components increase the risk of CHD and the multiplicative interactions between them were assessed using hazard ratios (HRs) and 95% confidence intervals (CIs). Additive interactions were appraised by the relative excess risk due to interaction, synergy index (SI), and attributable proportion of interaction. RESULTS: A total of 304 CHD patients were enrolled from rural residents of Xinjiang. Elevated blood pressure (HR 1.81; 95% CI 1.35-2.44) and elevated fasting blood glucose (FBG) (HR 1.82; 95% CI 1.38-2.38) increased the risk of CHD after adjustment for confounding factors. We found a positive additive interaction (SI 1.14; 95% CI 0.51-2.51) between elevated blood pressure and elevated FBG, but none were significant. As the number of components increased, the risk of CHD increased. The combinations of [high triglycerides (TG) + low high-density lipoprotein cholesterol (HDL-C) + elevated FBG + large waistline] (HR 4.26; 95% CI 1.43-12.73) and [elevated blood pressure + elevated FBG + low HDL-C + large waistline] (HR 1.82; 95% CI 1.38-2.38) increased the risk of CHD. CONCLUSIONS: We provide evidence that elevated blood pressure and elevated FBG are independent risk factors for CHD and it might be necessary to maintain the normal waistline for preventing CHD.

External validation of three atherosclerotic cardiovascular disease risk equations in rural areas of Xinjiang, China.

BACKGROUND: To externally validate the Prediction for ASCVD Risk in China (PAR) risk equation for predicting the 5-year atherosclerotic cardiovascular disease (ASCVD) risk in the Uyghur and Kazakh populations from rural areas in northwestern China and compare its performance with those of the pooled cohort equations (PCE) and Framingham risk score (FRS). METHODS: The final analysis included 3347 subjects aged 40-74 years without CVD at baseline. The 5-year ASCVD risk was calculated using the PAR, PCE, and FRS. Discrimination, calibration, and clinical usefulness of the three equations in predicting the 5-year ASCVD risk were assessed before and after recalibration. RESULTS: Of 3347 included subjects, 1839 were female. We observed 286 ASCVD events in within 5-year follow-up. All three risk equations had moderate discrimination in both men and women. C-indices of PAR, PCE, and FRS were 0.727 (95% CI, 0.725-0.729), 0.727 (95% CI, 0.725-0.729), and 0.740 (95% CI, 0.738-0.742), respectively, in men; the corresponding C-indices were 0.738 (95% CI, 0.737-0.739), 0.731 (95% CI, 0.730-0.732), and 0.761 (95% CI, 0.760-0.762), respectively, in women. PCE, PAR and FRS substantially underestimated the 5-year ASCVD risk in women by 70, 23 and 51%, respectively. However, PAR and FRS fairly predicted the risk in men and PAR was well calibrated. The calibrations of the three risk equations could be changed by recalibration. The decision curve analyses demonstrated that at the threshold risk of 5%, PCE was the most clinically useful in both men and women after recalibration. CONCLUSIONS: All three risk equations underestimated the 5-year ASCVD risk in women, while PAR and FRS fairly predicted that in men. However, the results of predictive performances for three risk equations are inconsistent, more accurate risk equations are required in the primary prevention of ASCVD aiming to this Uyghur and Kazakh populations.

Structure and Transport Properties in Itinerant Antiferromagnet RE2(Ni1- xCu x)5As3O2 (RE = Ce, Sm).

We report the crystal structure and physical properties of two Ni5As3-based compounds RE2Ni5As3O2 (RE = Ce, Sm). The former exhibits structural phase transition from tetragonal (space group I4/ mmm, 139) to orthorhombic (space group Immm, 71) symmetry at 230 K, while the latter undergoes a charge-density-wave-like structural distortion with abrupt change of Ni-As bond length. Both compounds show antiferromagnetic transitions due to RE3+ ions ordering at 4.4 and 3.4 K, accompanying with the large enhancement of Sommerfeld coefficients comparing to the nonmagnetic La analogue. Although the Cu substitution for Ni induces structural anomalies and suppression of structural transition like the behaviors in La/Pr/Nd analogues, the superconductivity is not observed in both Cu-doped RE2Ni5As3O2 (RE = Ce, Sm) above 0.25 K. Our structural refinements reveal that the lacking of superconductivity in RE2(Ni1- xCu x)5As3O2 might relate to the anomalous increase of As height, h1.

Nomogram Based on Cytokines for Cardiovascular Diseases in Xinjiang Kazakhs.

BACKGROUND: This study involved the development of a predictive 5-year morbidity nomogram for cardiovascular diseases (CVD) in Xinjiang Kazakhs based on cytokine levels. METHODS: The nomogram was based on a baseline survey of the town of Nalati in the Kazakh Autonomous Prefecture of Xinjiang from 2009 to 2013. By 2016, we had monitored 1508 people for a median time of 5.17 years and identified CVD events in the study population by collecting case information from local hospitals. The study population was divided into the training (n = 1005) and validation cohorts (n = 503) in a 2 : 1 ratio. The area under the receiver operating characteristic curve (AUC) was used to verify the predictive accuracy of the nomogram. The result was assessed in a validation cohort. RESULTS: At the end of the study, the incidence of CVD in Xinjiang Kazakhs was found to be 11.28%. We developed a new nomogram to predict the 5-year incidence of CVD based on age, interleukin-6 (IL-6), and adiponectin (APN) levels, diastolic blood pressure, and dyslipidemia. The AUC for the predictive accuracy of the nomogram was 0.836 (95% confidence interval: 0.802-0.869), which was higher than that for IL-6 and APN. These results were supported by validation studies. CONCLUSIONS: The nomogram model can more directly assess the risk of CVD in Kazakhs and can be used for CVD risk assessment.

MicroRNA-217 attenuates intima-media complex thickness of ascending aorta measured by ultrasound bio-microscopy and inhibits inflammation and lipid metabolism in atherosclerotic models of ApoE-/- mice.

BACKGROUND: Little investigation was done to test the efficiency of microRNA-217 (miR-217) on atherosclerosis in vivo. METHODS: ApoE-/- mice were used to construct atherosclerotic models and ultrasound bio-microscopy (UBM) was applied to detect the intima-media thickness (IMT) of the ascending aorta. The serum level of miR-217 and correlation with IMT was investigated. After miR-217 mimic administration, the IMT, inflammation, and lipid-associated molecules were assayed. RESULTS: The serum level of miR-217 was reduced in ApoE-/- mice and showed a negative correlation with the IMT of the ascending aorta (r2 = 0.5899, p < 0.0001). miR-217 mimic administration attenuated IMT and down-regulated the level of serum triglyceride (TG), total cholesterol (TC), and low-density-lipoprotein cholesterol (LDL-C), while it could up-regulate high-density lipoprotein cholesterol (HDL-C). Inflammation relevant genes, such as F4/80, tumor necrosis factor (TNF)-α, interleukin (IL)-1, IL-6, and monocyte chemoattractant protein (MCP)-1, and lipid metabolism associated gene, such as LDL receptor, class A scavenger receptors (SR-A), scavenger receptor class B type I (SR-BI), CD36, ATP binding cassette subfamily A member 1 (ABCA1), and ATP binding cassette subfamily G member 1 (ABCG1) in the aorta were significantly down-regulated in miR-217 group when compared with atherosclerosis group. CONCLUSION: miR-217 could down-regulate IMT and modulate the inflammation and lipid metabolism process, which indicates that miR-217 could be a potential treatment option.

Usefulness of thyroglobulin in cervical lymph node fine-needle aspirations at initial thyroidectomy for the diagnosis of metastases in papillary thyroid cancer.

OBJECTIVE: To study the role of fine-needle aspiration biopsy and thyroglobulin measurement (FNAB-Tg) in diagnosing cervical lymph node (CLN) metastases in patients with papillary thyroid cancer (PTC) before thyroidectomy. METHODS: Ultrasonography (US)-guided FNAB was performed on 92 patients with PTCs with 105 CLNs before surgery. The wash-out of the FNAB-Tg level was detected. RESULTS: Based on the final pathology, 67 lymph nodes (LNs) were positive for metastasis, and 38 LNs were negative for metastasis. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of FNAB-Tg in thyroidectomized patients was 100%, 86.8%, 95.2%, 97.3%, and 95.2%, respectively. CONCLUSIONS: FNAB-Tg is a useful technique for diagnosing CLN metastasis of PTC before thyroidectomy.
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[Chromatism Analysis of Multispectral Imaging System Based on AOTF and Hardware Compensation Strategy].

In view of the existing chromatism in the AOTF multispectral imaging system causes different wavelength imaging clarity under different focal length , even under the fixed wavelength, due to the horizontal direction (diffraction) spectral broadening, which leads to clear horizontal lines and blurring vertical lines. This paper made a concrete analysis of the chromatism of AOTF, pointing out the causes of imaging blurring. According to the imaging characteristics of AOTF multispectral imaging system, this paper proposed an improved algorithm based on SSIM, which can be used to evaluate the image sharpness. The target of the original algorithm was two images (one as a reference image, the other one as the test image), while the algorithm proposed in this paper made similarity analysis between the adjacent lines in one target image, small similarity in change edges declares great contrast, thus the image is clearer. The image quality caused by chromatism in the AOTF multispectral imaging system can be compensated by automatic focusing system, which mainly based on this algorithm. It has small calculated amount and fast speed. The feasibility and practicability of the compensation strategy were verified through experiments. The results show that this strategy can effectively solve the image blurring caused by chromatism in the AOTF multispectral imaging system, which has an important application value.

[The Study on the Influence of Spectral Diffraction Efficiency Based on the Matching Network of Wide Spectrum AOTF].

Given that AOTF (Acousto-Optic Tunable Filter, AOTF) spectral imaging analyzer is widely used in a wide spectral region of the visible and infrared spectrum, the spectral bandwidth, diffraction efficiency and power efficiency of the AOTF need to be improved to meet higher standards. Ultrasonic transducer is the core component of AOTF. Its 3 dB working bandwidth determines the spectral diffraction range of AOTF, so it is making two different thicknesses high-low frequency ultrasonic transducer to improve AOTF spectral bandwidth on the same of the acousto-optic medium. Because between the operating frequency of ultrasonic transducer and input impedance there exists non-linear relationship, they have different input impedances at different frequencies. When the between driving signal source's output impedance and ultrasound transducer have mismatched, It would produce energy consumption and lead to cannot bring the maximum power transfer to the ultrasonic transducer, so that the spectral diffraction efficiency of AOTF is reduced, and it affected spectral imaging quality. So going through to study theoretical ultrasonic transducer impedance frequency characteristics deeply in this paper designed a new broadband impedance matching network, which has important application reference value of the spectral diffraction efficiency improving. By ADS simulation and actual matching circuit experimental test, experimental results show that impedance matching network' power efficiency reach to more than 90%, spectral diffraction efficiency get up to 90% in the 60~200 MHz bandwidth, and improve to spectral imaging quality within 420~1 150 nm waveband. The higher diffraction efficiency of the matching network has important implications for the current application AOTF based on spectral imaging technology.

Gold-Template-Assisted Mechanical Exfoliation of Large-Area 2D Layers Enables Efficient and Precise Construction of Moiré Superlattices.

Moiré superlattices, consisting of rotationally aligned 2D atomically thin layers, provide a highly novel platform for the study of correlated quantum phenomena. However, reliable and efficient construction of moiré superlattices is challenging because of difficulties to accurately angle-align small exfoliated 2D layers and the need to shun wet-transfer processes. Here, efficient and precise construction of various moiré superlattices is demonstrated by picking up and stacking large-area 2D mono- or few-layer crystals with predetermined crystal axes, made possible by a gold-template-assisted mechanical exfoliation method. The exfoliated 2D layers are semiconductors, superconductors, or magnets and their high quality is confirmed by photoluminescence and Raman spectra and by electrical transport measurements of fabricated field-effect transistors and Hall devices. Twisted homobilayers with angle-twisting accuracy of ≈0.3°, twisted heterobilayers with sub-degree angle-alignment accuracy, and multilayer superlattices are precisely constructed and characterized by their moiré patterns, interlayer excitons, and second harmonic generation. The present study paves the way for exploring emergent phenomena in moiré superlattices.

Observation of Two-Dimensional Type-II Superconductivity in Bulk 3R-TaSe2 by Scanning Tunneling Spectroscopy.

Here we report a low-temperature and vector-magnetic-field scanning tunneling microscopy/spectroscopy (STM/S) study on 3R-TaSe2. The sample surface was obtained by exfoliating a bulk 3R-TaSe2 single crystal in an ultrahigh-vacuum (UHV) chamber and then transferred in situ to STM. It was observed that the topmost layer shows a 3 × 3 charge density wave pattern at T = 4.2 K with metallic character in STS. The electronic characterization study by variable-temperature and magnetic field STS revealed that 3R-TaSe2 behaves as a type-II superconductor. More intriguingly, such superconductivity (SC) can survive under strong in-plane magnetic fields even up to 2.5 T and out-of-plane magnetic fields up to 0.7 T, exhibiting an anisotropic superconducting property. Temperature-dependent STS showed that 3R-TaSe2 undergoes a transition above 0.58 K. Our results may be important for understanding the intriguing SC properties of the 3R-phase van der Waals materials.

Anomalous enhancement of charge density wave in kagome superconductor CsV3Sb5 approaching the 2D limit.

The recently discovered kagome metals AV3Sb5 (A = Cs, Rb, K) exhibit a variety of intriguing phenomena, such as a charge density wave (CDW) with time-reversal symmetry breaking and possible unconventional superconductivity. Here, we report a rare non-monotonic evolution of the CDW temperature (TCDW) with the reduction of flake thickness approaching the atomic limit, and the superconducting transition temperature (Tc) features an inverse variation with TCDW. TCDW initially decreases to a minimum value of 72 K at 27 layers and then increases abruptly, reaching a record-high value of 120 K at 5 layers. Raman scattering measurements reveal a weakened electron-phonon coupling with the reduction of sample thickness, suggesting that a crossover from electron-phonon coupling to dominantly electronic interactions could account for the non-monotonic thickness dependence of TCDW. Our work demonstrates the novel effects of dimension reduction and carrier doping on quantum states in thin flakes and provides crucial insights into the complex mechanism of the CDW order in the family of AV3Sb5 kagome metals.

Interface Investigation on SiGe/Si Multilayer Structures: Influence of Different Epitaxial Process Conditions.

SiGe/Si multilayer is the core structure of the active area of gate-all-around field-effect transistors and semiconductor quantum computing devices. In this paper, high-quality SiGe/Si multilayers have been grown by a reduced-pressure chemical vapor deposition system. The effects of temperature, pressure, interface processing (dichlorosilane (SiH2Cl2, DCS) and hydrogen chloride (HCl)) on improving the transition thickness of SiGe to Si interfaces were investigated. The interface quality was characterized by transmission electron microscopy/atomic force microscopy/high-resolution X-ray diffraction methods. It was observed that limiting the migration of Ge atoms in the interface was critical for optimizing a sharp interface, and the addition of DCS was found to decrease the interface transition thickness. The change of the interfacial transition layer is not significant in the short treatment time of HCl. When the processing time of HCl is increased, the internal interface is optimized to a certain extent but the corresponding film thickness is also reduced. This study provides technical support for the acquisition of an abrupt interface and will have a very favorable influence on the performance improvement of miniaturized devices in the future.

Boosting CO2 Electroreduction via Construction of a Stable ZnS/ZnO Interface.

Carbon dioxide (CO2) electroreduction can offer a way of relieving environmental and energy issues. Gold and silver catalysts show considerable electrochemical performance for CO production; however, the electrochemical CO2 conversion to CO is still restricted by the Faradaic efficiency, current density, and stability over the catalysts. Non-noble metal (zinc) is considered as a promising catalyst for CO2 electroreduction because of its low cost. However, because of the electron-rich property of zinc, it has a weak adsorption capacity of intermediates, resulting in a poor CO2 electroreduction performance. In this work, ZnS nanoparticles are embedded onto the ZnO surface to construct a stable ZnS/ZnO interface structure. The ZnS/ZnO interface reaches a maximum current density of 327.2 ± 10.6 mA cm-2 with a CO Faradaic efficiency of 91.9 ± 0.6% at -0.73 V vs a reversible hydrogen electrode (RHE) and remains stable for 40 h at a current density of 115.7 ± 7.0 mA cm-2 with a CO Faradaic efficiency of 93.8 ± 3.7% at -0.56 V vs RHE.