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We report a controllable method to synthesize two different morphologies of two dimensional (2D) 1T′-MoTe2 film: rectangular MoTe2 and irregular MoTe2, respectively. The synthesis was carried out via chemical vapor deposition (CVD) with sodium chloride (NaCl) as promoters. Our results show that topography of rectangular MoTe2 nanosheets have more uniform thickness while irregular nanosheets have poorer crystallization quality with more grain boundaries. Moreover, the surface friction decreases with the increasing thickness of 2D MoTe2, owing to the gradually decreased surface corrugation of nanosheets as the thickness increase. Our work provides a feasible method to synthesize the challenging transition-metal dichalcogenides (TMDs).

The dosage of blast furnace slag (BFS) in cement is limited on account of relative low reaction rate and low early strength. Improving the early age activity of BFS is the fundamental solution for high volume BFS cementitious materials. Generally, mechanical activation is one of the main techniques to accelerate the early reaction of mineral admixtures. In this study, wet-milling and dry-separation are respectively used to prepare ultrafine BFS to improve its early reactivity. The early hydration characteristics, mechanical property, hydration products of ultrahigh volume BFS cementitious materials are analyzed to assess the efficiency of ultrafine BFS on the properties of BFS cement paste. The results show that the initial and final setting time both gradually decrease as the dry-separation BFS (GS) dosage increases, while the wet-milling BFS (WS) series present the opposite tendency. The electrical resistivity of WS specimens develops at a faster rate than that of GS specimens. Mixes containing WS, at a maximum dosage of 90%, have higher mechanical property than those with GS, resulting in an enhancement of strength. The hydration products mainly include calcium hydroxide, hydrotalcite, hydrotalcite-like phase, calcium carbonate, stratlingite, C-S-H, C-A-S-H, and akermanite.

PURPOSE We aimed to analyze the psychological status in breast cancer (BC) patients in the epicenter of the COVID-19 pandemic. PATIENTS AND METHODS A total of 658 individuals were recruited from multiple breast cancer centers in Hubei Province. Online questionnaires were conducted, and included demographic information, clinical features, and four Patient Reported Outcomes (PROs) scales (GAP-7, PHQ-9, ISI, and IES-R). Multivariable logistic regression analysis was designed to identify potential factors on mental health outcomes. RESULTS Questionnaires were collected from February 16 to 19, 2020, the peak time point of COVID-19 outbreak in China. 46.2% BC patients had to modify planned necessary anti-cancer treatment during the outbreak. 8.9% and 9.3% patients reported severe anxiety and severe depression, respectively. 20.8% and 4.0% patients showed severe distress and insomnia, respectively. Multivariable logistic regression analysis demonstrated poor general condition, shorter duration after BC diagnosis, aggressive BC molecular subtypes and close contact with COVID-19 patients as independent factors associated with anxiety. Poor general condition and CVC (central venous catheter) flushing delay were independently association factors depression. In terms of insomnia, poor generation condition was the only associated independent factor. Poor physical condition and treatment discontinuation were underlying risk factors for distress based on multivariable analysis. CONCLUSION High rates of anxiety, depression, distress, and insomnia were observed in patients with breast cancer during the COVID-19 outbreak. Special attention should be paid to psychological status of breast cancer patients especially those with poor general condition, treatment discontinuation, aggressive molecular subtypes and metastatic breast cancer., During the COVID-19 outbreak in China, fear about COVID-19, together with worry about progression of cancer, cause strong emotion stress in cancer patients. We evaluated patient reported outcome in 658 breast cancer patients and survivors recruited from multiple breast cancer centers in Hubei Province using four standardized assessment scales. Multivariable logistic regression analysis was used to identify potential affecting factors on mental health outcomes. High rates of anxiety, depression, distress, and insomnia were observed in patients with breast cancer during the COVID-19 outbreak. Based on our results, living in Wuhan, poor general condition by self-identification, shorter duration after breast cancer diagnosis, aggressive breast cancer molecular subtypes, metastatic breast cancer clinical stage, treatment discontinuation, CVC flushing delay, or close contact with COVID-19 patients are associated risk factors for poorer psychological status. Special attention should be paid to psychological status of breast cancer patients especially those with poor general condition, treatment discontinuation, aggressive molecular subtypes and metastatic breast cancer.

Chemical vapor deposition (CVD) method was used to grow large area and layer controllable WS2 film. Our results show that the as grown WS2 film is an excellent substrate for surface enhanced Raman scattering (SERS). The Raman enhancement effect depends crucially on the layer number of WS2 film: monolayer WS2 offers the strongest Raman signal, and the Raman enhancement effect gradually decreases with the increase in the layer number of WS2. Further analysis indicates that this transition originates from the charge transfer yield between the R6G molecules and the underlying WS2 substrate.

The aim of this paper is to evaluate the self-hydration characteristic of GGBFS activated by wet-grinding treatment (WGT). Three slag slurries with different fineness were prepared through milling with varying duration (20 min, 40 min and 60 min, abbreviated as S2, S4 and S6, respectively). The reaction kinetics, mechanical properties, hydration products and microstructure of hardened GGBFS pastes were analyzed to assess the effect of WGT on the self-hydration process of GGBFS. The results indicated that self-hydration was achieved after grinding without chemical activation and the rate of self-hydration was improved with the increased grinding duration. The setting times were dramatically shortened and the compressive strength was notably increased when prolonging the grinding time. The hydration process of GGBFS slurry after 20 min milling included incubation period, but the others did not. The electrical resistivity development of samples S2 and S4 decreased during the initial period, followed by setting, acceleration and deceleration stage. However, sample S6 exhibited an absence of the initial stage. The self-hydration products analyses indicated that the main products were calcium silicate hydrate, calcium aluminosilicate hydrate (C-A-S-H), hydrotalcite, akermanite and calcite.

Engineering an advanced noble-metal-free electrocatalyst for boosting hydrogen evolution reaction (HER) is highly desired, but remains a challenging task. In this work, hierarchical porous particle-on-sheet CoP was synthesized through direct gas-solid phosphorization of bi-compositional Co(OH)2/ZIF-67 precursor. This special morphology endows the hybrid CoP(C/Z) catalysts with more exposed active sites and favorable charge and ion transport pathways. Furthermore, the collective CoP units derived from two kinds of precursors would regulate the electronic structure and enhance the intrinsic activity of active site. As a consequence, the composition-optimized CoP(C/Z)-0.6 electrocatalyst could deliver superior activity towards HER with low overpotentials of 154 mV and 181 mV to achieve 10 mA cm-2 and 20 mA cm-2 current densities, a maximum TOF value of 0.0477 s-1, a Tafel slope of 85.1 mV dec-1, as well as good stability in alkaline electrolyte. This present study may shed light on the exploration of transition-metal phosphides with compositional and structural complexity for enhancing the electrocatalytic ability.

To achieve photoelectric appliance, effective carrier separation is a vital question. Here, we construct van der Waals (vdW) heterostructure by superimposing two different two-dimensional (2D) layer materials BP and AlN via vdW force. The results show that 2D BP/AlN heterostructure exhibits direct band gap characteristics and has a type-II band alignment, which accelerates the effective separation of electron-hole pairs. In addition, under the modulation of applied external electric field and biaxial strain, this heterostructure still keeps a type-II band alignment. This result reveals that 2D BP/AlN heterostructure shows a wide application prospect in the future photoelectric nanodevices.

The adsorption of precursor material to liquid metal allows it to be used to control film growth in chemical vapor deposition (CVD) method. Here, growth mechanism of two dimensional (2D) WS 2 film were investigated by CVD method with liquid Au modulation. During the growth process, the liquid Au adsorbs W-precursor and it serves as a W-oxide reservoir to release its internal W-oxide to the surface of substrate. Thus, this technology can affect the film growth by controlling the surrounding “local W-precursor concentration”. In the outward direction centering on the liquid Au, the size of 2D WS2 film increases first and then decreases. Besides, the thickness of WS2 film in the region influenced by liquid Au increases significantly. This result provides a new idea for controllable growth of 2D material .

Porous Pt-doping heterojunctions, Pt-ZnO-Co3O4, Pt-ZnS-CoS, and Pt-Zn3P2-CoP were fabricated by firstly the oxidation, sulfurization, and phosphorization of ZnCo-zeolitic-imidazolate-framework (ZnCo-ZIF) and then the doping of Pt nanoparticles. They exhibit excellent photocatalytic activity towards hydrogen generation from water splitting. These bimetallic metal-organic-framework (MOF) derivatives maintain the porous framework skeleton of ZnCo-ZIF precursor, there by significantly enhancing the light utilization and simultaneously affording abundant exposed catalytic active sites. Most importantly, suitable band matching and strong electron coupling in these heterojunctions are achieved by using the bimetallic MOF template, which facilitate the efficient electron-hole separation and transportation. In addition, Pt nanoparticles distributed on the porous heterojunctions as electron traps can offer rich redox active sites for the hydrogen generation. Correspondingly, the hydrogen generation rate of Pt-ZnO-Co3O4, Pt-ZnS-CoS, and Pt-Zn3P2-CoP was up to ~7.80, ~8.21, and ~9.15 mmol h−1 g−1, respectively, higher than those of respective ZIF-8 or ZIF-67-based derivatives. This work thus provides a new approach that using bimetallic MOF as template directs the fabrication of noble-metal doping heterojunctions to simultaneously enhance light absorption utilization, electro-hole separation, and transport, therefore promoting surface water oxidation reaction for efficient water splitting.

The electron transport properties of zigzag graphene nanoribbons (ZGNRs) with upright standing carbon chains are investigated by using first-principles calculations. The calculated results show a significant odd-even dependence. The currents of even-numbered chain configurations are small because a suppression emerges around the Fermi energy in the transmission spectra under a finite bias. However the I − V curves of odd-numbered chain structures display metallic properties with a big transmission peak in the transmission spectra, indicating the high conductance. These properties offer an interesting method by modifying the odd-even parity of the carbon chains to tune the electron transport properties of ZGNRS.

Er3+-M2+ (M2+ = Zn2+, Mg2+) co-doped double-perovskite CaBa2WO6 phosphors were synthesized. The site occupancy of Mg2+and Zn2+ is studied by first-principles calculations of binding energy, the band structure and partial density of states. The temperature dependent emission spectra of resulting samples are studied. The fluoresce intensity ratio of thermally coupled levels of 2H11/2 and 4S3/2 is dependent on the temperature. The optical temperature sensitivity of perovskite CaBa2WO6:Er3+ is doubled by co-doping with 3 mol% Mg2+. These results indicate that CaBa2WO6:Er3+, Mg2+ will be applied in optical temperature sensor.

Synthesis of monolayer transition metal dichalcogenides (TMDs) in large-size is crucial to their practical applications in electronics and optoelectronics. Here, large scale continuous monolayer WS2 film has been successfully grown by atmospheric pressure chemical vapor deposition (APCVD) method. By modulating three growth parameters, Ar gas flow rate, the temperature of WO3 precursor and the distance between substrate and WO3 precursor, WS2 film with different grain size can be obtained. At optimal processing condition, large-scale monolayer WS2 with lateral dimension can reach 1 mm above. This would pave the way for scale production of continuous monolayer TMDs film.

Exploring materials formation mechanism and shape evolution during the growth of nanomaterials is vital for controllable synthesis and improving the crystal quality. Here, two dimensional WS 2 films were synthesized on Si/SiO2 substrates via atmospheric pressure chemical vapor deposition . Different shapes of WS 2 films scattered on the surface of substrate can be obtained simultaneously under the same experimental condition. We find that the edge free energy of different edges competes with each other, which promotes the growth of two dimensional WS2. Besides, the local ratio between W and S atoms of precursors on the surface of substrates can also influence the growth process and the final morphology of WS2 films. This work is helpful in further understanding the growth mechanism of 2D films and then further modulating the quality of 2D materials .