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The performance of organic solar cells (OSCs) can be greatly improved by incorporating silica-coated gold nanorods (Au@SiO 2 NRs) at the interface between the hole transporting layer and the active layer due to the plasmonic effect. The silica shell impedes the aggregation effect of the Au NRs in ethanol solution which otherwise would bring forward serious reduction in the open circuit voltage when incorporating the Au NRs at the buffer/active interface. As a result, while the high open circuit voltage being demonstrated, the optimized plasmonic OSCs possess an increased short circuit current, and correspondingly an elevated power conversion efficiency with the enhancement factor of ~11%. The origin of performance improvement in OSCs with the Au@SiO 2 NRs was analyzed systematically using morphological, electrical, optical characterizations along with theoretical simulation. It is found that the broadband enhancement in absorption, which yields the broadband enhancement in exciton generation in the active layer, is the major factor contributing to the increase in the short circuit current density. Simulation results suggest that the excitation of the transverse and longitudinal surface plasmon resonances of individual NRs as well as their mutual coupling can generate strong electric field near the vicinity of the NRs, thereby an improved exciton generation profile in the active layer. The incorporation of Au@SiO 2 NRs at the buffer/active interface also improves hole extraction in the OSCs, resulting in an increase in the open circuit voltage along with a decrease in the series resistance.

A novel patterning methodology is reported for fabricating complex polymer brush micropatterns with a spatially controllable 3D nanostructure and chemical composition.

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NO emission is a significant source of pollutant from coal combustion. With the establishment of industry flue gas emission standards, removal of NO has been attracting attention and research globally. In this paper, the denitration process through the use of a FeII complex solvent has been studied based on the approach of the wet desulfurization method. The kinetic parameters of the chemical reaction for NO absorption by FeII complex have also been deduced to provide theoretical consideration for the feasibility of this process. It is demonstrated that FeIIEDTA adsorbs NO efficiently under the conditions investigated, achieving the maximum NO reduction efficiency at a neutral pH value at 50 °C. The inlet O2 content in flue gas is a crucial factor affecting the performance of FeII complex, the increment in which leads to the oxidation of FeII into FeIII and hence reduces the absorption capability of the sorbent. The coexistence of SO2 and NO in flue gas decreases the NO removal efficiency by being preferentially adsorbed by the sorbent. However, with the increasing content of SO2 in flue gas, the solvent’s capability in absorbing NO is recovered to its original level.

Two types of magnetic nanocomposites, Co‐carbon composite (Co@C) and Zn/Co‐carbon composite (Zn/Co@C), were synthesized by one‐step calcinations of hollow Co‐ZIF (ZIF‐67) and Zn/Co‐ZIF (ZIF‐67@ZIF‐8) (ZIF = zeolitic imidazolate framework), as well as applied as adsorbents in the reduction of Rhodamine B (RhB). The prepared composites were carefully analyzed by SEM, TEM‐EDXS (EDXS = energy‐dispersive X‐ray specroscopy), XRD, SQUID, and nitrogen adsorption/desorption measurements. Co@C and Zn/Co@C showed the maximum adsorption capacities of 48 mg g–1 and 101.93 mg g–1, respectively, toward RhB. The adsorption isotherms of RhB on the Zn/Co@C nanocomposites were well fitted with the Langmuir model, and the pseudo‐second‐order model accurately describes the adsorption kinetic process for the adsorption of RhB on the materials. The results show that the composite materials of Zn/Co@C possess higher porosity and magnetic properties and exhibit higher adsorption capacity, convenient separation ability, along with good reusability of the adsorbent. The theoretical calculations also clarify that RhB on the distorted Co–Zn surface is much more stable than that on Co(111), in good agreement with the experimental observations.

Magnetic nitrogenous cobalt-carbon composites were synthesized via calcination of N-ZIF-67, where metal and N atoms were introduced into the conductive carbon matrix formed during carbonization of N-ZIF-67, and were applied, as catalysts, in the reduction reaction of p-nitrophenol, assisted by NaBH. Characterization of the prepared composites was carefully performed using SEM, TEM, XRD, SQUID magnetometric analysis, XPS and nitrogen adsorption/desorption measurements. Compared to Co@C, which was similarly prepared, the N-Co@C catalyst exhibits much better catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol. The pseudo-first-order rate constant for the N-Co@C catalyst is 4.47 times greater than that for the Co@C catalyst, and its stability shows little change after five reaction cycles. The superior catalytic properties of the N-Co@C catalyst are due to the presence of N moieties. Leaching out the cobalt cores was induced using FeCl and HCl to see what the active centers were. The results show that the majority of the catalytic activity is associated with the metal cores.