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With a dual strategy of phase-interface engineering, monolayer (1L)–1T-WSe2 integrated with Ag2Se nanoparticles (NPs) is in situ fabricated as quasi-monolayer Ag2Se/1L–1T-WSe2 hybrid nanosheets via a one-pot oleylamine-colloidal reaction. The Ag2Se NPs direct the growth of 1L–1T-WSe2 nanosheets forming the quasi-monolayer hybrid nanosheets by lodging in the interlayer spaces of WSe2 while the Ag2Se NPs being in a superionic conductor state diffuse rapidly and prevent the growth of piled-up multilayered WSe2 nanosheets. Due to the formation of quasi-monolayer Ag2Se/1L–1T-WSe2 nanosheets, many more side edges are exposed. Intensive studies illustrated that the quasi-monolayer Ag2Se/1L–1T-WSe2 hybrid nanosheets provide increased surface area and active sites as compared with isolated Ag2Se and WSe2. The hybrid nanosheets demonstrated excellent catalytic properties for hydrogen evolution reaction (HER) with overpotentials (η10) of 163 and 140 mV in acidic and basic conditions, respectively, and an outstanding alkaline supercapacitance of 1674 F g–1 at 1 A g–1. Meanwhile, X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) determinations revealed that the quasi-monolayer hybrid nanosheets with enhanced electronic modulation could promote H+ adsorption/H2 desorption and accelerate the transport and separation of charge on the interface of heterostructured catalyst along with the electrode surface so as to exhibit outstanding electrochemical performances for HER and pseudocapacitance. [ABSTRACT FROM AUTHOR]

Weak‐light photodetection shows considerable potential in both theoretical and technical aspects while it would be a key issue to explore new candidate materials for practical application in view of high reliability and durability of the devices under ambient conditions. In this work, Ag2HgS2 single crystal rods (SCRs) with length up to 1.2 cm and width ranging from 10 to 200 µm are successfully fabricated in pure phase via facile solvothermal process at 200 °C for 24 h for the first time. The Ag2HgS2 SCRs are technically investigated, and the study reveals that they are in high quality via the determination of their crystal structure, morphology, and optical properties. Density functional theory (DFT) calculations are carried out to explore more reliably details on the band structure of bulk Ag2HgS2. Meanwhile, a series of photodetectors based on the individual Ag2HgS2 SCRs are fabricated, and they convey sensitive responses to a 0.170 µW cm−2 weak light and unanimous responses to incident light with different wavelengths from 254 to 980 nm. In addition, the devices show excellent detecting performances without any obvious slump after the Ag2HgS2 SCRs exposed in air over 18 months. [ABSTRACT FROM AUTHOR]

Iron vanadate (FeVO4 ) was synthesized by a co-precipitation method and was firstly used as an adsorbent for the removal of Cu2+ from aqueous solution. The effects of operating parameters on the adsorption of Cu2+ by FeVO4 such as contact time, temperature, solution pH and initial concentration of Cu2+ were investigated. Kinetic study exhibited that the adsorption of Cu2+ onto FeVO4 followed a pseudo-second-order model and was controlled by the film diffusion with a small contribution of intraparticle diffusion. The equilibrium data could be well fitted with the Langmuir isotherm, indicating a monolayer adsorption process. The mean free energy E (kJ mol–1) got from the D–R isotherm also suggested the chemisorption nature of the adsorption process. The desorption study showed that 95% and 98% of Cu2+ was desorbed from FeVO4 using 0.1 M of HNO3 and 0.1 M of EDTA, respectively. Moreover, the maximum adsorption capacity of FeVO4 toward Cu2+ is 55.6 mg g–1 at pH 5.0, which is higher than most of the adsorbents reported in the same pH range. The results indicate that FeVO4 is a promising adsorbent for the removal of Cu2+ from waste effluents. [ABSTRACT FROM AUTHOR]

In this study, the sorption behavior ofPleurotus ostreatustoward Ni(II) is examined with respect to pH, temperature, contact time, and concentration. The good correlation coefficient and close agreement between experimental and theoretical values of biosorption capacity confirm that the pseudo-second-order kinetic model is best applicable to the kinetics data. The sorption of Ni(II) is found to be dependent upon the pH and temperature of the solution. The adsorption of Ni(II) ontoP. ostreatusis maximum at higher pH values and decreases with an increase in temperature in the range of 298–318 K. BothXmandKbvalues decrease with increase in temperature, indicating the exothermic nature of the process. Different thermodynamic parameters were calculated for adsorption of Ni(II) ontoP. ostreatus. The negative value of ΔSindicates a decrease in randomness at the solid/liquid interface. The values of isosteric heat of adsorption are decreasing with increases in surface coverage, which reveal the heterogeneous nature of the solid surface. The FTIR spectra show that the carbonyl groups ofP. ostreatusare responsible for adsorption of Ni(II) ontoP. ostreatus. [ABSTRACT FROM PUBLISHER]

Biosorpt ion of Mn (II) from aqueous solut ion by P. Ostreatus was invest igated at different concentrations, pH and temperature. The close agreement between the experimental and theoretical biosorption capacity confirmed that Pseudo 2nd order equat ion is best fitted to the present experimental data. The biosorption capacity of P. Ost reatus was observed to be dependent upon the pH and temperature of adsorpt ion system. The values of biosorpt ion maxima (Xm) and binding energy constant (Kb) were observed to decrease with rise in temperature in the range of 298 - 323K. The negative values of ΔG and ΔH showed the process of Mn (II) biosorpt ion onto P. Ost reatus is spontaneous and exothermic respectively. Similarly, the values of isosteric heat of biosorption (ΔD) were decreased with increase in surface coverage (e) which indicated that the surface of the P. Ostreatus is energet ically heterogeneous in nature. [ABSTRACT FROM AUTHOR]

Manganese-based chalcogenides would be of latent capacity in serving as anodes for assembling lithium- and/or sodium-ion batteries (LIBs/SIBs) due to their large theoretical capacity, low price, and low-toxicity functionality, while the low electroconductivity and easy agglomeration behavior may impede their technical applications. Here, a solid-state solution of MnS 0.5 Se 0.5 nanocubes in rock-salt phase has been synthesized for the first time at a relatively low temperature from the precursors of Mn(II) acetylacetonate with dibenzyl dichalcogens in oleylamine with octadecene, and the MnS 0.5 Se 0.5 nanocubes have been assembled with N-doped graphene to form a new kind of heterostructured nanohybrids (shortened as MnS 0.5 Se 0.5 /N-G hybrids), which are very potential for the fabrication of metal-ion batteries including LIBs and/or SIBs. Investigations revealed that there have been dense vacancies generated and active sites increased via nonequilibrium alloying of MnS and MnSe into the solid-solution MnS 0.5 Se 0.5 nanocubes with segregation and defects achieved in the low-temperature solution synthetic route. Meanwhile, the introduction of N-doped graphene forming heterojunction interfaces between MnS 0.5 Se 0.5 and N-doped graphene would efficiently enhance their electroconductivity and avoid agglomeration of the active MnS 0.5 Se 0.5 nanocubes with considerably improved electrochemical properties. As a result, the MnS 0.5 Se 0.5 /N-G hybrids delivered superior Li/Na storage capacities with outstanding rate performance as well as satisfactorily lasting stability (1039/457 mA h g -1 at 0.1 A g -1 for LIBs/SIBs). Additionally, full-cell LIBs of the anodic MnS 0.5 Se 0.5 /N-G constructed with cathodic LiFePO 4 (LFP) further confirmed the promising future for their practical application.