Molecularly imprinted photocatalyst with a structural analogue of template and its application

Targeted degradation of refractory organic compounds in wastewaters based on molecular imprinting catalysts

Efficient removal of low-concentration refractory pollutants is a crucial problem to ensuring water safety. The use of heterogeneous catalysis of molecular imprinting technology combined with traditional catalysts is a promising method to improve removal efficiency. Presently, the research into molecular imprinting targeting catalysts focuses mainly on material preparation and performance optimization. However, more researchers are investigating other applications of imprinting materials. This review provides recent progress in photocatalyst preparation, electrocatalyst, and Fenton-like catalysts synthesized by molecular imprinting. The principle and control points of target catalysts prepared by precipitation polymerization (PP) and surface molecular imprinting (S-MIP) are introduced. Also, the application of imprinted catalysts in targeted degradation of drugs, pesticides, environmental hormones, and other refractory pollutants is summarized. In addition, the reusability and stability of imprinted catalyst in water treatment are discussed, and the possible ecotoxicity risk is analyzed. Finally, we appraised the prospects, challenges, and opportunities of imprinted catalysts in the advanced oxidation process. This paper provides a reference for the targeted degradation of refractory pollutants and the preparation of targeted catalysts.

Recent Advances in Nanomaterials Based Molecularly Imprinted Electrochemical Sensors

Nanotechnology and molecular imprinting both are omnipresent in the modern scientific world. Molecular recognition in the biological systems was mimicked to an extreme extent with its difficulties through molecular imprinting. Solving the problems related to this mimicking was the goal of science and technology. Some challenges like difficulties with the imprinting of protein, poor compatibility with aqueous environments, template leakage, and heterogeneous populations of binding sites in the polymers that contribute to a high level of nonspecific binding sites were addressed with recent advancement in the modern era. These issues were solved later with nano level instrumentations and inventions. Different types of nanomaterials were employed for this research on molecular recognition through MIPs to enhance selectivity, sensitivity and stability to specific systems such as sensors. This review paper attempts to give all the recent advances in molecular imprinting and the potential of nanomaterials in electrochemical sensors.

Preparation of water-compatible molecularly imprinted thiol-functionalized activated titanium dioxide: Selective adsorption and efficient photodegradation of 2, 4-dinitrophenol in aqueous solution

A novel water-compatible surface molecularly imprinted thiol-functionalized titanium dioxide (TiO₂) material (CMIP-coated TiO₂) was prepared in water, using 2, 4-dinitrophenol (2, 4-DNP) as template molecule and o-phenylenediamine (OPDA) as both functional monomer and cross-linker. The as-synthesized materials were characterized by FESEM, FTIR, XRD, BET and UV-vis DRS. Moreover, we have investigated the adsorption capacity, adsorption selectivity and photodegradation activity of the CMIP-coated TiO₂ and non-molecular imprinted materials (CNIP-coated TiO₂). Additionally, the effects of pH and concentration of 2, 4-DNP on the degradation rate of 2, 4-DNP were also investigated. Results showed that CMIP-coated TiO₂ exhibited higher adsorption capacity, greater selectivity and faster photodegradation activity for 2, 4-DNP compared with the CNIP-coated TiO₂. Meanwhile, the specific selectivity to 2, 4-DNP over its structural analogue 4-nitrophenol (4-NP) and the enhanced photodegradation capacity were mainly attributed to the imprinted cavities on the surface of CMIP-coated TiO₂. Taking advantage of efficient removal capacity, high reusability and no-additional chemicals in imprinted process, the prepared materials can be potentially applied to "green" removal of 2, 4-DNP in wastewater.

A convenient approach of MIP/Co–TiO2 nanocomposites with highly enhanced photocatalytic activity and selectivity under visible light irradiation

MIP/Co–TiO₂ nanocomposites were synthesized. Their mechanisms of preferable photocatalytic activity and good selectivity for target contaminants were identified and discussed.

Specific oriented recognition of a new stable ICTX@Mfa with retrievability for selective photocatalytic degrading of ciprofloxacin

A new imprinted photocatalyst ICTX@Mfa which exhibits superior specific oriented recognition capability, stability and retrievability for selectively degrading ciprofloxacin.

Sol-hydrothermal synthesis of inorganic-framework molecularly imprinted TiO2/SiO2 nanocomposite and its preferential photocatalytic degradation towards target contaminant

Inorganic-framework molecularly imprinted TiO2/SiO2 nanocomposite (MIP-TiO2/SiO2) was successfully prepared by sol-hydrothermal method using 4-nitrophenol as template. The morphology, structure, optical property, zeta-potential and photocurrent of MIP-TiO2/SiO2 were characterized. The adsorption performance and photocatalytic selectivity were also studied. MIP-TiO2/SiO2 shows higher adsorption capacity and selectivity than the non-imprinted TiO2/SiO2 (NIP-TiO2/SiO2). Kinetics results show that the adsorption equilibrium of 4-nitrophenol on MIP-TiO2/SiO2 is established within 20 min, and the adsorption process obeys the pseudo-second-order model. Moreover, MIP-TiO2/SiO2 can completely degrade 4-nitrophenol within 30 min, while NIP-TiO2/SiO2 takes 110 min. It was found that the MIP-TiO2/SiO2 photocatalyst shows molecular recognition ability, leading to selective adsorption and molecular recognitive photocatalytic degradation of 4-nitrophenol. Furthermore, because of its inorganic framework, MIP-TiO2/SiO2 shows excellent reusability.

Particle-assisted semidirect breath figure method: a facile way to endow the honeycomb-structured petri dish with molecular recognition capability

Recently, we have developed a semidirect breath figure (sDBF) method for direct fabrication of large-area and ordered honeycomb structures on commercial polystyrene (PS) Petri dishes without the use of an external polymer solution. In this work, we showed that both the pore size and the pore uniformity of the breath figure patterns were controllable by solvent amount. The cross-sectional image shows that only one layer of pores was formed on the BF figure patterns. By combing the sDBF method and Pickering emulsion and using the modular building blocks, we endowed the honeycomb-structured Petri dish with molecular recognition capability via the decoration of molecularly imprinted polymer (MIP) nanoparticles into the honeycomb pores. The radioligand binding experiments show that the MIP nanoparticles on the resultant honeycomb structures maintained high molecular binding selectivity. The reusability study indicates that MIP-BF patterns had excellent mechanical stability during the radioligand binding process. We believe that the modular approach demonstrated in this work will open up further opportunities for honeycomb structure-based chemical sensors for drug analysis, substrates for catalysts, and scaffold for cell growth.