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Development of highly sensitive and selective fluorescent sensors toward hazardous analytes represents great progress in fabricating sensing devices for practical applications. In this work, a highly selective sensor with dual functions has been fabricated via facile postmodification of the UiO-MOF. Butene modified salicylaldehyde is covalently linked to the UiO-66 scaffold via an efficient Schiff-base reaction, resulting in a highly fluorescent ozone sensor of UiO-66-butene. Ozonolysis of the terminal olefin followed by β-elimination could significantly quench the bright blue fluorescence of UiO-66-butene, and linear turn-off detection of ozone in the range of 0-100 μM is well established. The detection is highly sensitive and selective, and a detection limit of 73 nM was calculated. Remarkably, the ozonolysis afforded product could further act as a selective sensor for Al3+ via turn-on fluorescence with a detection limit of 142 nM, representing a second potential sensing function. The chemically selective sequential ozonolysis/β-elimination and remarkable dual functions offer the exclusive detection of ozone over other oxidative species as well as Al3+ over other cations following a tandem process, representing the first example of a direct MOF sensor for dual sensing of ozone and Al3+. This work demonstrates the potential of employing combinatorial principles for fabricating highly selective sensors, and postmodification of MOFs represents a promising facile strategy for developing various functional sensors.

TiO2 nanotube-based photocatalytic concrete paving block was prepared, and its mechanical properties, including compressive strength and abrasion resistance, as well as photocatalytic removal of NO, were investigated. Results indicate that the compressive strength and abrasion resistance of photocatalytic concrete paving block were obviously reinforced by TiO2 nanotubes compared with TiO2 nanoparticles, which might derive from the enhanced binding force between TiO2 nanotubes and calcium–silicate–hydrate (C–S–H) gel derived from the cement hydration. Moreover, the TiO2 nanotube-based photocatalytic concrete paving block shows the best photocatalytic removal of NO among the as-prepared samples, which might result from the enhanced adsorption property for NO gas over TiO2 nanotubes, and little change of NO conversion was found before and after polishing. Overall, TiO2 nanotubes not only contribute to the reinforcement of mechanical properties of the concrete block, but also dedicated to the enhancement of photocatalytic performance for NO purification.

Developing a low cost but efficient photocatalyst with maximum utilization of sunlight, minimum charge carrier recombination and improved stability is very crucial and challenging. Triphenylphosphine modification of HKUST-1 followed by controlled calcination resulted in a phosphorus doped carbon/Cu2O composite (HKUST-1-P-300). The structure and band properties were fully studied, and phenol degradation and H2 evolution were employed to evaluate the photocatalytic activity. Under visible light irradiation, HKUST-1-P-300 showed superior photocatalytic activity and stability. A phenol degradation efficiency of up to 99.8% was achieved within 90 minutes, and also a remarkable H2 evolution rate of 1208 μmol was achieved. The external quantum efficiency of solar hydrogen evolution over this photocatalyst, without noble metal loading, reaches 48.6% at 425 nm. More auspiciously, the photocatalytic reaction continued for more than 12 h without performance degradation. To get further evidence for the origin of the improved photocatalytic activity of the HKUST-1-P-300, a series of characterization studies have been carried out. To the best of our knowledge, this work represents the first example of using P-doped carbon/Cu2O both for phenol degradation and H2 production. Mechanistic studies were carried out to give insights into the photodegradation process, and the superior photocatalytic activity of HKUST-1-P-300 can be ascribed to enhanced visible light absorption efficiency, higher surface area, efficient separation of photogenerated charge carriers, reduced aggregation of Cu2O and the synergistic effect of the P-doped carbon/Cu2O structures. This work demonstrates a facile and promising approach for designing low cost, highly stable and efficient heterostructured photocatalysts that can be applicable for energy and environmental applications.

A two-stage scheduling robust predictive control (RPC) algorithm, which is based on the time-varying coefficient information of the state-dependent ARX (SD-ARX) model, is designed for the output tracking control of a class of nonlinear systems. First, by using the parameter variation range information of the SD-ARX, a strategy for constructing the system’s polytopic model is designed. To further reduce the conservativeness of the convex polytopic sets which are designed to wrap the system’s future dynamics, the variation range information of the SD-ARX model’s parameters is also considered and compressed. In this method, the polytopic state-space model of the system is constructed directly based on the special structure of the SD-ARX model itself, and there is no need to make such assumption that the bounds on the parameter’s variation range in the system model are known or measurable. And then, a two-stage scheduling RPC algorithm is designed for the output tracking control. A numerical example is presented to demonstrate the effectiveness of the proposed RPC strategy.

It is of great significance to exploit environmentally friendly, efficient and economical catalysts for dealing with wastewater and other aquatic environments. In this study, a series of P-doped Cu/Cu2O/C heterostructures were obtained by controlled calcination of corncobs supported Cu-MOF in different temperature. Comprehensive structural characterizations indicate the polyhedron morphology and high porosity of HKUST-1-P@corncob-400. The composites were further explored as an efficient catalyst for catalytic reduction of 4-nitrophenol (4-NP). Remarkably, HKUST-1-P@corncob-400 could efficiently catalyze the reduction of 4-NP, and the reduction could be finished within 90 s with a 4-aminophenol (4-AP) selectivity of >99%, demonstrating the excellent performance of Cu-based catalysts for 4-NP reduction. The application scope could be further expanded to the catalytic reduction of ofloxacin and a conversion of 95.7% could be achieved within 10 min. Reproducibility studies and characterizations comprehensively demonstrate the promising potential of HKUST-1-P@corncob-400 acting as efficient catalyst for the reductive removal of environmental pollutants. This work provides a facile strategy for the fabrication of highly active catalysts for high-performance environmental purification, and the employment of renewable bioresources and functional MOFs represents a promising strategy for design and synthesis of highly active catalysts towards various advanced applications.

Traditional CO2 sensing technologies suffer from the disadvantages of being bulky and cross-sensitive to interferences such as CO and H2O, these issues could be properly tackled by innovating a novel fluorescence-based sensing technology. Metal–organic frameworks (MOFs), which have been widely explored as versatile fluorescence sensors, are still at a standstill for aggregation-induced emission (AIE), and no example of MOFs showing a dynamic AIE activity has been reported yet. Herein, we report a novel MOF, which successfully converts the aggregation-caused quenching of the autologous ligand molecule to be AIE-active upon framework construction and exhibits bright fluorescence in a highly viscous environment, resulting in the first example of MOFs exhibiting a real dynamic AIE activity. Furthermore, a linear CO2 fluorescence quantification for mixed gases in the concentration range of 2.5–100% was thus well-established. These results herald the understanding and advent of a new generation in all solid-sta...