Search

Rigid, solid-state components represent the current paradigm for electronic systems, but they lack post-production reconfigurability and pose ever-increasing challenges to efficient end-of-life recycling. Liquid electronics may overcome these limitations by offering flexible in-the-field redesign and separation at end-of-life via simple liquid phase chemistries. Up to now, preliminary work on liquid electronics has focused on liquid metal components, but these devices still require an encapsulating polymer and typically use alloys of rare elements like indium. Here, using the self-assembly of jammed two-dimensional titanium carbide (Ti

We report the selective removal of perchlorate from water by a cationic coordination polymer in the highest observed capacity and rate to date. Silver bipyridine acetate [Ag(4,4′-bipy)+][CH3CO2–]·6H2O (bipy = bipyridine) is easily synthesized in water under ambient conditions (60 min with 99.1% yield). The material releases its environmentally benign acetate anions upon perchlorate uptake to 99.9% mol/mol completion in Millipore water. Actual contaminated industrial water from an underground plume (53 ppm initial perchlorate concentration) was treated to 96% mol/mol in 60 min. The uptake capacity is near-record high at 310 mg/g and is 94% complete within 30 min. Perchlorate exchange was also conducted at 1–30 ppm perchlorate typical of underground contaminated source sites, with up to 99.7% mol/mol completion.

An in-depth study of the class of cationic materials [Ag(4,4'-bipy)+][X-] (where X- = CH3CO2-, NO3-, BF4-, ClO4-, and MnO4-) has led to key insights on the relationship between anion hydration energy, material structure, solubility, and stability. Since these materials show promise for their potential as water remediation tools, understanding their properties in detail is of significant importance. The structure of the starting and ending materials is the main driving force behind the resultant stability and solubility and can be successfully used to predict the ion exchange capabilities. The solubility trend was determined to be, from most soluble to least soluble, X- = CH3CO2- > NO3- ∼ BF4- > ClO4- > MnO4-. Kinetics and thermal stability also follow predictable trends but involve additional factors. For instance, the kinetics of NO3- to MnO4- exchange was much slower than expected based on that seen for NO3- to ClO4-. Powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the materials. Solubility was determined by inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis. Ion exchange was analyzed with ion chromatography (IC) and ultraviolet-visible spectroscopy (UV-vis), and thermal stability was determined with thermogravimetric analysis (TGA).