A new review article examines opportunities and practical challenges that nanotechnology applications pose in addressing the guiding principles for a green economy. There is a general perception that nanotechnologies will have a significant impact on developing 'green' and 'clean' technologies with considerable environmental benefits. The associated concept of green nanotechnology aims to exploit nanotech-enabled innovations in materials science and engineering to generate products and processes that are energy efficient as well as economically and environmentally sustainable.
The adoption of a newly developed, facile synthesis method in catalyst designs may permit the rapid screening of nanoalloys for water contaminants. Given the compositional dynamics of this technique, a series of nanoalloys with different surface compositions can be quickly synthesized using a single starting solution and the optimal metal ratio experimentally determined to find the best catalytic reactivity for degrading the pollutant.
One of the problems with activated carbon is the disposal of adsorbed contaminants along with the adsorbent. Another concern is that its pores are often blocked during adsorption. By contrast, carbon nanotubes' (CNTs) open structure offers easy, undisrupted access to reactive sites located on nanotubes' outer surface. That's why researchers see CNTs as an attractive potential substitute for activated carbon. Researchers now have demonstrated that individual CNTs can be integrated into micrometer-sized colloidal particles without using a heavy or bulky particulate support.
Concern about the depletion of global water resources has grown rapidly in the past decade due to our increasing global population and growing demand for other diverse applications. Since only 2.5% of the Earth's water is fresh, it has been reported that almost half of the world's population is at risk of a water crisis by the year 2025. Accordingly, significant research efforts have been focused on the desalination of brackish/seawater and the remediation and reuse of wastewater to meet the agricultural, industrial, and domestic water demands.
Individual graphene sheets and their functionalized derivatives have been used to remove metal ions and organic pollutants from water. These graphene-based nanomaterials show quite high adsorption performance as adsorbents. However they also cause additional cost because the removal of these adsorbent materials after usage is difficult and there is the risk of secondary environmental pollution unless the nanomaterials are collected completely after usage. One solution to this problem would be the assembly of individual sheets into three-dimensional (3D) macroscopic structures which would preserve the unique properties of individual graphene sheets, and offer easy collecting and recycling after water remediation.
In microbial fuell cells, the anode material as the medium of electron transfer and as the support for biofilm formation is a key component that determines the effectiveness and efficiency of power generation. Generally, the anode will perform better if the anode material has a greater specific surface area and higher affinity for living bacterial cells. The direct carbonization of low-cost and naturally available materials provides a potential alternative to commercial anodes with high specific surface area. In new work, scientists demonstrate a new procedure to generate novel macroporous carbon prepared from a fibrous loofah sponge.
The construction of artificial micro- and nanomotors is a high priority in the nanotechnology field owing to their great potential for diverse potential applications, ranging from targeted drug delivery, on-chip diagnostics and biosensing, or pumping of fluids at the microscale to environmental remediation. In new work, researchers have now reported the first example of micromotors for the active degradation of organic pollutants in solution. The novelty of this work lies in the synergy between internal and external functionality of the micromotors.
Every year, large quantities of antibiotics are released into lakes and rivers as a byproduct of their use in farming and medicine. Antibiotics in the environment can select for antibiotic-resistant bacterial populations, which can cause severe infections if they come into contact with humans or animals. In addition, antibiotics can disrupt the natural bacterial flora that plays a vital role in maintaining the balance of ecosystems. Scientists have now found that solar-powered proteoliposomes derived from bacteria can extract and store contaminants released into natural bodies of water,