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Monoclinic Lu2WO6 undergoes diphase-to-perovskite BiLuWO6 transition via selective occupancy of Bi in three Lu sites. The transformation mechanism, process, and structure stabilities are revealed by variable cell nudged elastic band method, video, and phonon spectrum. Lattice transition brings about photogenerated charge separation in BiLuWO6. This is verified by indirect band gap transition, high electron migration rate, weak exciton binding energy, large photocurrent response, and small impedance. The electron–hole life time is elongated to produce abundant superoxide and hydroxyl radicals for the degradation of rhodamine B and phenol molecules. Bi–O antibonding states serve as immediate energy levels to change the recombination path, inducing 340 nm excitation band and 510 nm green light emission of Lu2WO6. Furthermore, multicolor emission of 1 at% Bi3+ + RE3+ (RE = Sm/Eu/Dy)-codoped Lu2WO6 is acquired via synergistic modification of the Bi–O antibonding state and RE3+ 4f states. Thus, the photogenerated charge motion in Lu2WO6 is tuned to expand application fields.

The 4f band gap states (BGSs) of Dy and Eu ions play an important role in luminescence and energy transfer in monoclinic Lu2WO6. The corresponding white and red light emissions were ascribed to ele...

Thirteen BaTiO3/γ-Bi2O3 heterojunctions (labeled as HS1 to HS13) were synthesized via solid phase method under different raw material ratio, calcination temperatures, and times with XRD, SEM, EDS mapping, TEM, XPS, and Raman spectra characterizations. The degradation efficiency of all samples is above 93% after 90 min upon initial concentration 10 mg/L tetracycline with the optimal HS6 as 97.95%. The first order reaction rate is above 0.059 min-1, faster than 0.031 min-1 of BaTiO3 and 0.011 min-1 of γ-Bi2O3. The catalyst masses, different water bodies, and pH values have a little effect on the final removal efficiency of tetracycline. Under the same test environment, the removal efficiency of 10 mg/L rhodamine B is over 73.62%, higher than BaTiO3 45.35% and γ-Bi2O3 63.34% and the best HS3, HS4, and HS5 samples have 100% degradation efficiency. The heterojunction can be recycled with excellent structural stability. The superior catalytic activity is attributed to electrons transfer along Z-type from γ-Bi2O3 conductor band (CB) to BaTiO3 valence band (VB) via work function and charge density difference analysis. The superoxide radical and hole are active substance in the process of tetracycline degradation while the rhodamine B removal is ascribed to superoxide and hydroxyl radicals attacking. The decomposition paths of two pollutants are revealed using high performance liquid chromatography mass spectroscopy (HPLC-MS).

Heterojunction composite plays an important role in enhancing photocatalysis activity through inhibit electron-hole recombination. In this paper, biphasic heterojunction BiVO4 and HoVO4 is insitu-grown and characterized through XRD, TEM, Raman, SEM, EDS, and XPS. These two structures form n type staggered band configuration using Mott-Schottky and DRS. Rhodamine B (RhB) photodegradation efficiency of the optimal sample is 90.7% after 90 min, higher than single BiVO4 54% and HoVO4 34.5%. The main reason is ascribed to fast photogenerated charge separation via O O bond connection according to photoluminescence, photocurrent response, and theory calculation. The RhB degradation path is revealed from intermediate products identification. Therefore this study unveils photodegradation dyes application of BiVO4/HoVO4 samples.

Molecular orbital theory predicts that interactions between lone-pair electrons give rise to van der Waals forces between layers due to the nonequivalent hybridization in bulk black phosphorus. First-principles calculations show that phosphorene nanoribbons (PNRs) have a high activity and can be bonded easily with oxygen atoms and hydroxyl groups, indicating that the PNRs can be oxidized easily. The cliff PNR configuration can be maintained when it is passivated with hydroxyl groups, indicating that it could be stable in a strong alkaline environment. Upon oxidation of their zigzag, armchair, and cliff edges, phosphorene nanoribbons can be changed from semimetallic to semiconducting, and the band gap can be changed from direct to indirect. OHO- [(OH + O)-] and OH- [(O + H)-] passivated PNRs have intrinsic spin magnetic moments of approximately 2.00 μB, which originate from the edge unsaturation electrons and the symmetry reduction. Therefore, oxidized PNRs might have potential applications in photoelectro...

In this work, graphene oxide quantum dots (GOQDs) are introduced as an electron-trapped layer in Pd/Zr[Formula: see text]Hf[Formula: see text]O2 (ZHO)/SiO2/Si memory device. This structure possessed longer than 104 s retention capability, a low operation voltage around [Formula: see text][Formula: see text]V and 2.61[Formula: see text]V storage windows. GOQDs contained carbon–carbon and carbon–oxygen single/double bonds based on the analysis of C-1[Formula: see text] and O-1[Formula: see text] X-ray photoelectron spectra. It is proposed that the GOQDs’ wide bandgap with many oxygen-containing functional groups favors charge capture to a greater extent. This new type of charge-trapping memory can be a promising candidate for wide application to storing information with non-volatility in the big data era.