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We have successfully synthesized two kinetically stable CuI-MOFs with 2D layered architectures by introduction of β-[Mo8O26]4− clusters, denoted as [CuI2(β-Mo8O26)(bnie)2][Cu2(bnie)2] (NAU-1) and [CuI2(bnie)2]2(β-Mo8O26) (NAU-2) respectively. According to the result of electrochemical analysis, all these framework active materials behave as pseudo-capacitor and exhibit high capacitance and excellent energy delivery efficiency. For instance, the maximum gravimetric capacitance of NAU-1 and NAU-2 electrode is 800 and 828 F g−1 at a current density of 1.0 A g−1 separately. Theory mechanism analyses suggest capacitive (i ∝ v) and diffusion-controlled (i ∝ v1/2) currents contribute equally during redox reaction process. Particularly, after integration of carbon-based conductive matrix with CuI-MOFs, the structural stability and cycling life are both promoted. Whether carbon nanotubes or graphene oxide, they both boost the conductivity of the electrode and the capacitance retentions of these electrodes keep growing trends that all surpass 100% after 5000 continuous cycles. The excellent electrochemical performance may be ascribed to the β-[Mo8O26]4− clusters occupying the void space of 2D layered structures that facilitate electron transport and ions transmission.

A semiempirical model for bacterial growth and bioleaching of Acidithiobacillus spp. was developed based on the concept of transport phenomena. Only one mathematical equation and three parameters evaluated from the experimental data are required to describe the complicated bioleaching process, regardless of the source and concentration of the microorganism, the concentration, composition, and physical characteristics (particle size, shape, distribution, and porosity, etc.) of the solid substrate, the concentrations of the leaching products and byproducts, and the leaching conditions (pH, temperature, agitation, etc.). In order to evaluate the semiempirical model, five kinetic models proposed previously were compared. The results of mean deviations show that our model fits their experimental data explicitly well, even better than the corresponding models. Furthermore, the semiempirical model can be successfully used to predict the bacterial growth and bioleaching behaviors in different leaching systems, i.e. direct, indirect, direct and indirect, and simultaneous leaching.

Biosorption of each of the heavy metals, Zn(II) and Cu(II), and of the binary mixture of these two metal ions by the indigenous Thiobacillus thiooxidans was investigated in this study. Equilibrium concentration (qm) and dissociation constant (Kd) were calculated by fitting the experimental data with the Langmuir isotherms. The effects of pH, pretreatment of biomass, and temperature on the amount of metal uptake by this organism were also determined. Typically, the adsorption capacity increases with increasing pH in the ranges of 2.0–6.0 and 4.0–5.0 for Zn(II) and Cu(II), respectively. Chemical pretreatment of the biomass with 0.075 M NaOH has positive effects on its capacity for metal biosorption. Higher temperature yields higher biosorption capacity for both metals. The indigenous T. thiooxidans is in favor of Zn(II) uptake in the binary mixture. Biosorption of Cu(II) is inhibited by the existence of Zn(II). The total amount of metal adsorbed in the binary mixture decreases in comparison with biosorption of only one kind of metal ion.