Understanding the nature of interactions between inorganic surfaces and biomolecules, such as amino acids and peptides, can enhance the development of new materials. Here, we present single molecule force spectroscopy (SMFS) measurements of the interactions between an atomic force microscopy (AFM) probe, modified with various amino acids, and a titanium dioxide surface. Specifically, we study the affinity of amino acids toward a titanium dioxide surface bearing hydrophobic (Leu), aromatic (Phe) and hydrophilic (Orn) residues. We find that aromatic interactions dominate over aliphatic in their affinity to the titanium dioxide surface. In addition, we show that by combining aromatic and hydrophilic moieties in a single amino acid (NH2-Phe), the adhesion of the latter to the surface increases. Furthermore, the affinity of positively charged amino acids to the titanium dioxide surface is higher than that of uncharged, and can be increased more, with elevating the pH of the buffer above the pK(a) of the basic residues. The kinetic and thermodynamic parameters imply that the dynamics of the surface-amino acid interface are mostly governed by hydrophobic interactions.

The nuclear disasters of Chernobyl and Fukushima presented an urgent need for finding solutions to treatment of radioactive wastes. Among the by-products of nuclear fission is radioactive Cs-137, which evokes an environmental hazard due to its long half-life (> 30 years) and high solubility in water. In this work, a water-soluble organic ligand, readily obtained from alloxan and 1,3,5-benzenetriol, has been found to selectively bind and precipitate Cs+ ions from aqueous solutions. The special rigid structure of the ligand, which consists of a ‘‘tripodal’’ carbonyl base above and below an aromatic plane, contributes to the size-driven selectivity towards the large Cs+ ions and the formation of a giant, insoluble supramolecular complex. In addition to the low costs of the ligand, high yields and effectiveness in precipitating Cs+ ions, the Cs- complex revealed a high endurance to continuous doses of gamma-radiation, increasing its potential to act as a precipitating agent for Cs-137.

Controlling the permeability and porosity of an inorganic layer using biomolecule building blocks has raised interest for nanotechnological applications. The challenge lies mostly in the fabrication, usually a long, expensive and tedious process, involving many steps. Using biomaterials for this purpose is highly appealing; due to both ease of fabrication and the final output, that contains a bioelement. The biomolecule, specifically, stable protein 1 (SP1), serving as the scaffold for our pattern, is of great stability and durability, and presents size, charge and structural selectivity towards electroactive species. Here, we demonstrate the ability of SP1 to form a rigid template within a sol-gel matrix, allowing selective electron transfer to the gold electrode. Specifically, a thiolated SP1 was first adsorbed on a gold surface followed by filling the non-occupied areas by sol-gel. The latter was electrochemically deposited. The various steps were carefully characterized. Finally, we studied the electrochemistry of numerous redox couple at the Au/SP1/sol-gel interface and found that the nanochannel array shows charge and structural selectivity, which is based on the interactions between the redox species and the functionalities of SP1. The resulted surface shows promise towards electrochemical sensing applications.

The development of printed electronics has gained much attention as an alternative for conventional metal-based electronics, mainly due to the ability to print electronic circuits on plastics and by much cheaper means as compared with conventional microelectronics. Here we report on a single stage formation of a highly corrosion resistance coating with hydrophobic properties on printed-Cu nanoparticles. Our method is based on the synergistic effect of benzotriazole (BTA) as corrosion inhibitor and trimethylsiloxysilicate (TMS) as hydrophobic component. Printed-Cu coated with such TMS/BTA layer exhibited excellent corrosion resistance in 3.5% NaCl solution, reducing the dissolution of Cu into soluble species by one order of magnitude.

More than 50% of solar energy comes from the infrared region (as radiant heat) of the solar spectrum. Electrochromic (EC) materials, which can dynamically modulate the transmittance of infrared (IR) radiation, can be effectively applied in smart windows for thermal management in buildings. In this work, a core-shell TiO2-WO3 inverse opal (IO) structure was fabricated through the electrodeposition of WO3 onto TiO2 IO templates. The TiO2 IO templates were synthesized by introducing TiO2 into the voids of a polystyrene (PS) colloidal crystal template, followed by calcination to remove the PS microspheres. It was found that the TiO2-WO3 IO core-shell structure can modulate NIR transmittance at wavelengths from 700 to 1600 nm in the NIR range when potential is applied in LiClO4/PC electrolyte. When -0.3 V is applied, up to 60% of NIR radiation in this range can be blocked. The NIR transmittance can be modulated by tuning the applied potential. This study focuses on comparing the novel TiO2-WO3 IO structure with electrodeposited WO3 thin film to fully elucidate the effect of the inverse opal morphology and the TiO2-WO3 hybrid system on the optical properties. Results show that the NIR blockage can be sustained up to 90% after 1200 reversible cycles for TiO2-WO3 IO structure. The greater surface area of the IO structure increases the number of active sites available for the redox reactions by providing a larger contact area with the electrolyte. The more electroactive area with improved charge transfer enhances the overall NIR transmittance contrast as compared to bulk WO3 thin film. Furthermore, the addition of WO3 to TiO2 to form a composite has been shown to enhance cycling performance and device lifespan.

This paper focus on defining a research question while conducting action research among third-year students attending a course on Research Literacy at a teacher education college. This paper discusses the process of preparing for and conducting action research among third-year students attending a course on Research Literacy at a teacher education college. The students were asked to conduct an action research on their classroom activities. The aim of this article is to present the process and pinpointing the discomfort of the students in formulating a research question suited to action research thanks to two prerequisite conditions: the ‘safe space’ and the ‘tender spot’. The research findings illustrate that the students had difficulty defining their ‘ tender spot’. It was necessary to create a ‘safe space’. Furthermore, the findings show that the ‘tender spot’ issues were associated with disciplinary content far more than with generic lesson management or classroom management issues. The approach discussed here is leading to positive change and it may be that this professional development tool can facilitate the induction of novice teachers everywhere.

Biofouling, the adsorption of organisms to a surface, is a major problem today in many areas of our lives. This includes: (i) health, as biofouling on medical device leads to hospital-acquired infections, (ii) water, since the accumulation of organisms on membranes and pipes in desalination systems harms the function of the system, and (iii) energy, due to the heavy load of the organic layer that accumulates on marine vessels and causes a larger consumption of fuel. This paper presents an effective electrochemical approach for generating antifouling and antimicrobial surfaces. Distinct from previously reported antifouling or antimicrobial electrochemical studies, we demonstrate the formation of a hydrogen gas bubble layer through the application of a low-voltage square waveform pulses to the conductive surface. This electrochemically generated gas bubble layer serves as a separation barrier between the surroundings and the target surface where the adhesion of bacteria can be deterred. Our results indicate that this barrier could effectively reduce the adsorption of bacteria to the surface by 99.5%. We propose that the antimicrobial mechanism correlates with the fundamental of hydrogen evolution reaction (HER). HER leads to an arid environment that does not allow the existence of live bacteria. In addition, we show that this drought condition kills the preadhered bacteria on the surface due to water stress. This work serves as the basis for the exploration of future self-sustainable antifouling techniques such as incorporating it with photocatalytic and photoelectrochemical reactions.

The electrochemically triggered release of doxorubicin (DOX) from flexible electrodes modified electrophoretically with reduced graphene oxide (rGO)-DOX is reported. The release is driven by a positive potential pulse that decreases the pH of the rGO-DOX surface locally, which is confirmed by scanning electrochemical microscopy (SECM) in situ. In vitro cell viability tests confirms that the delivery system meets therapeutic needs.