A graphene oxide (GO) membrane is supported on a ceramic hollow fiber prepared by a vacuum suction method. This GO membrane exhibited excellent water permeation for dimethyl carbonate/water mixtures through a pervaporation process. At 25 °C and 2.6 wt % feed water content, the permeate water content reached 95.2 wt% with a high permeation flux (1702 g m(-2) h(-1)).

The extraction and subsequent separation of individual rare earth elements (REEs) from REE-bearing feedstocks represent a challenging yet essential task for the growth and sustainability of renewable energy technologies. As an important step toward overcoming the technical and environmental limitations of current REE processing methods, we demonstrate a biobased, all-aqueous REE extraction and separation scheme using the REE-selective lanmodulin protein. Lanmodulin was conjugated onto porous support materials using thiol-maleimide chemistry to enable tandem REE purification and separation under flow-through conditions. Immobilized lanmodulin maintains the attractive properties of the soluble protein, including remarkable REE selectivity, the ability to bind REEs at low pH, and high stability over numerous low-pH adsorption/desorption cycles. We further demonstrate the ability of immobilized lanmodulin to achieve high-purity separation of the clean-energy-critical REE pair Nd/Dy and to transform a low-grade leachate (0.043 mol % REEs) into separate heavy and light REE fractions (88 mol % purity of total REEs) in a single column run while using ∼90% of the column capacity. This ability to achieve, for the first time, tandem extraction and grouped separation of REEs from very complex aqueous feedstock solutions without requiring organic solvents establishes this lanmodulin-based approach as an important advance for sustainable hydrometallurgy.

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For the first time, a ZIF-8 membrane was grown on the inner surface of a ceramic hollow fiber via cycling precursors. The inner-side hollow fiber ZIF-8 membrane exhibits good performance for recovering hydrogen.

Technologically critical rare-earth elements are notoriously difficult to separate, owing to their subtle differences in ionic radius and coordination number1–3. The natural lanthanide-binding protein lanmodulin (LanM)4,5 is a sustainable alternative to conventional solvent-extraction-based separation6. Here we characterize a new LanM, from Hansschlegelia quercus (Hans-LanM), with an oligomeric state sensitive to rare-earth ionic radius, the lanthanum(III)-induced dimer being >100-fold tighter than the dysprosium(III)-induced dimer. X-ray crystal structures illustrate how picometre-scale differences in radius between lanthanum(III) and dysprosium(III) are propagated to Hans-LanM’s quaternary structure through a carboxylate shift that rearranges a second-sphere hydrogen-bonding network. Comparison to the prototypal LanM from Methylorubrum extorquens reveals distinct metal coordination strategies, rationalizing Hans-LanM’s greater selectivity within the rare-earth elements. Finally, structure-guided mutagenesis of a key residue at the Hans-LanM dimer interface modulates dimerization in solution and enables single-stage, column-based separation of a neodymium(III)/dysprosium(III) mixture to >98% individual element purities. This work showcases the natural diversity of selective lanthanide recognition motifs, and it reveals rare-earth-sensitive dimerization as a biological principle by which to tune the performance of biomolecule-based separation processes.

A graphene oxide (GO) membrane is supported on a ceramic hollow fiber prepared by a vacuum suction method. This GO membrane exhibited excellent water permeation for dimethyl carbonate/water mixtures through a pervaporation process. At 25 8C and 2.6 wt % feed water content, the permeate water content reached 95.2 wt % with a high permeation flux (1702 g m À2 h À1 ).

Smart surfaces that can dynamically respond to environmental stimuli have demonstrated great promise in wearable electronics and optical detectors. Herein, a photopatternable nanolayered polymeric film that can reversibly display and hide structural colors in the visible range in response to relative humidity (RH) changes is reported. This film is fabricated on a silicon substrate using layer-by-layer assembly of chitosan and photoreactive carboxymethyl cellulose-azido derivative, and selectively crosslinked through UV irradiation from a photomask. Compared to crosslinked regions, un-crosslinked ones swell more and result in a larger thickness at high RH; as a result, those two regions show distinguishable color differences. The correlation of displayed color with film thickness at various RHs is plotted in an International Commission on Illumination (CIE) chromaticity diagram, which is in good agreement with the results obtained from modeling based on the interference theory. It is demonstrated that the structural color patterns on the film can be hidden and displayed spontaneously by contact with humid air, including human breath.This humidity-triggered color change is fast, of fine resolution, highly reversible, and compatible with most silicon-based devices. This film is low-cost, stable, and ready to be applied to large surface areas for potential applications in anticounterfeiting, humidity sensors, and optical color filters.

Demystifying the elusive chemistry of actinium leads to novel opportunities in radioisotope production and nuclear medicine.