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Every year vast quantities of silver are lost in various waste streams; this, combined with its limited, diminishing supply and rising demand, makes silver recovery of increasing importance. Thus, herein, we report a controllable, green process to produce a host of highly porous metal–organic framework (MOF)/oligomer composites using supercritical carbon dioxide (ScCO2) as a medium. One resulting composite, referred to as MIL‐127/Poly‐o‐phenylenediamine (PoPD), has an excellent Ag+ adsorption capacity, removal efficiency (>99 %) and provides rapid Ag+ extraction in as little as 5 min from complex liquid matrices. Notably, the composite can also reduce sliver concentrations below the levels (<0.1 ppm) established by the United States Environmental Protection Agency. Using theoretical simulations, we find that there are spatially ordered polymeric units inside the MOF that promote the complexation of Ag+ over other common competing ions. Moreover, the oligomer is able to reduce silver to its metallic state, also providing antibacterial properties. [ABSTRACT FROM AUTHOR]

Metal halide perovskite ferroelectrics combining spontaneous polarization and excellent semiconducting properties is an ideal platform for enabling self‐driven X‐ray detection. However, achievements to date have been only based on uniaxiality, which increases the complexity of device fabrication. Multi‐axial ferroelectric materials have multiple equivalent polarization directions, making them potentially amenable to multi‐axial self‐driven X‐ray detection, but the report on these types of materials is still a huge blank. Herein, a high‐quality (BA)2(EA)2Pb3I10 (1) biaxial ferroelectric single crystal was successfully grown, which exhibited significant spontaneous polarization along the c‐axis and b‐axis. Under X‐ray irradiation, bulk photovoltaic effect (BPVE) was exhibited along both the c‐axis and b‐axis, with open circuit voltages (Voc) of 0.23 V and 0.22 V, respectively. Then, the BPVE revealed along the inversion of polarized direction with the polarized electric fields. Intriguingly, due to the BPVE of 1, 1 achieved multi‐axial self‐driven X‐ray detection for the first time (c‐axis and b‐axis) with relatively high sensitivities and ultralow detection limits (17.2 nGyair s−1 and 19.4 nGyair s−1, respectively). This work provides a reference for the subsequent use of multi‐axial ferroelectricity for multi‐axial self‐driven optoelectronic detection. [ABSTRACT FROM AUTHOR]

Every year vast quantities of silver are lost in various waste streams; this, combined with its limited, diminishing supply and rising demand, makes silver recovery of increasing importance. Thus, herein, we report a controllable, green process to produce a host of highly porous metal–organic framework (MOF)/oligomer composites using supercritical carbon dioxide (ScCO2) as a medium. One resulting composite, referred to as MIL‐127/Poly‐o‐phenylenediamine (PoPD), has an excellent Ag+ adsorption capacity, removal efficiency (>99 %) and provides rapid Ag+ extraction in as little as 5 min from complex liquid matrices. Notably, the composite can also reduce sliver concentrations below the levels (<0.1 ppm) established by the United States Environmental Protection Agency. Using theoretical simulations, we find that there are spatially ordered polymeric units inside the MOF that promote the complexation of Ag+ over other common competing ions. Moreover, the oligomer is able to reduce silver to its metallic state, also providing antibacterial properties. [ABSTRACT FROM AUTHOR]