A 3D porous Cu current collector is fabricated through chemical dealloying from a commerial Cu–Zn alloy tape. The interlinked porous framework naturally integrated can accommodate Li deposition, ...suppressing dendrite growth and alleviating the huge volume change during cycling. The Li metal anode combined with such a porous Cu collector demonstrates excellent performance and commerial potentials in Li‐based secondary batteries.
The development of lithium (Li) metal anodes Li metal batteries faces huge challenges such as uncontrolled Li dendrite growth and large volume change during Li plating/stripping, resulting in severe ...capacity decay and high safety hazards. A 3D porous copper (Cu) current collector as a host for Li deposition can effectively settle these problems. However, constructing a uniform and compact 3D porous Cu structure is still an enormous challenge. Herein, an electrochemical etching method for Cu–Zinc (Zn) alloy is reported to precisely engrave a 3D Cu structure with uniform, smooth, and compact porous network. Such a continuous structure endows 3D Cu excellent mechanical properties and high electrical conductivity. The uniform and smooth pores with a large internal surface area ensures well dispersed current density for homogeneous Li metal deposition and accommodation. A smooth and stable solid electrolyte interphase is formed and meanwhile Li dendrites and dead Li are effectively suppressed. The Li metal anode conceived 3D Cu current collector can stably cycle for 400 h under an Li plating/stripping capacity of 1 mA h cm−2 and a current density of 1 mA cm−2. The Li@3D Cu||LiFePO4 full cells present excellent cycling and rate performances. The electrochemical dealloying is a robust method to construct 3D Cu current collectors for dendrite‐free Li metal anodes.
The electrochemical etching method is presented to prepare 3D Cu with a uniform and compact porous network. As current collector of Li metal anode, the 3D Cu with large internal surface area and enhanced mechanical properties can effectively accommodate Li metal and suppress Li dendrite growth to achieve a high performance in a Li–metal battery.
The advent of SELEX (systematic evolution of ligands by exponential enrichment) technology has shown the ability to evolve artificial ligands with affinity and specificity able to meet growing ...clinical demand for probes that can, for example, distinguish between the target leukemia cells and other cancer cells within the matrix of heterogeneity, which characterizes cancer cells. Though antibodies are the conventional and ideal choice as a molecular recognition tool for many applications, aptamers complement the use of antibodies due to many unique advantages, such as small size, low cost, and facile chemical modification. This Minireview will focus on the novel applications of aptamers and SELEX, as well as opportunities to develop molecular tools able to meet future clinical needs in biomedicine.
Advantages of aptamers and SELEX in diverse research fields are summarized in this Minireview, along with some limitations and possible solutions to them. Furthermore described are future perspectives for aptamer modification with a near‐infinite number of molecular‐modulating elements that will result in more powerful tools in bioscience.
All‐solid‐state lithium metal battery is the most promising next‐generation energy storage device. However, the low ionic conductivity of solid electrolytes and high interfacial impedance with ...electrode are the main factors to limit the development of all‐solid‐state batteries. In this work, a low resistance–integrated all‐solid‐state battery is designed with excellent electrochemical performance that applies the polyethylene oxide (PEO) with lithium bis(trifluoromethylsulphonyl)imide as both binder of cathode and matrix of composite electrolyte embedded with Li7La3Zr2O12 (LLZO) nanowires (PLLN). The PEO in cathode and PLLN are fused at high temperature to form an integrated all‐solid‐state battery structure, which effectively strengthens the interface compatibility and stability between cathode and PLLN to guarantee high efficient ion transportation during long cycling. The LLZO nanowires uniformly distributed in PLLN can increase the ionic conductivity and mechanical strength of composite electrolyte efficiently, which induces the uniform deposition of lithium metal, thereby suppressing the lithium dendrite growth. The Li symmetric cells using PLLN can stably cycle for 1000 h without short circuit at 60 °C. The integrated LiFePO4/PLLN/Li batteries show excellent cycling stability at both 60 and 45 °C. The study proposed a novel and robust battery structure with outstanding electrochemical properties.
A low resistance–integrated all‐solid‐state Li metal battery with excellent electrochemical performance is designed. The structure not only guarantees high ionic conductivity and good mechanical properties to suppress lithium dendrite growth by using polyethylene oxide (PEO)/lithium bis(trifluoromethylsulphonyl)imide embedded with Li7La3Zr2O12 nanowire composite electrolyte, but also decreases the interfacial impedance by applying PEO in both electrolyte and cathode that can fuse during operation.
Restricted by the poor ability of polymers to dissociate lithium salts and transport ions, solid‐state polymer electrolytes (SPEs) show extremely low ionic conductivities (≈10−7–10−5 S cm−1) and ...transference number of lithium ions (tLi+ ≈0.2–0.4) at 25 °C. Here, a novel polymer matrix of SPEs that simultaneously promotes lithium salt dissociation and ion transportation based on a high dielectric poly(vinylidene fluoride‐trifluoroethylene‐chlorotrifluoroethylene) (TerP) and an all‐trans conformational poly(vinylidene fluoride‐trifluoroethylene) (CoP), is developed. The high dielectric constant increases the polarity of CH2CF2 polar groups; then, brings a strong electronegative end that dissociates Li+ from lithium salts. The all‐trans conformation assures all fluorine atoms locate on one side of the chain, constructing ion hopping highways. As a result, the TerP/CoP (TC) SPE exhibits a high ionic conductivity (2.37 × 10−4 S cm−1) and a quite large tLi+ of 0.61 at 25 °C. The Li/TC SPE/Li symmetric cells cycle stably for more than half a year (>4500 h) and the LiNi0.8Co0.1Mn0.1O2/TC SPE/Li cell cycles steadily for 1000 and 600 cycles at 1 C and 2 C at 25 °C, respectively. This work paves a new way to prepare high‐performance SPEs by simultaneously modulating dielectric constants and conformation of polymers.
Through conformational regulation of the high dielectric P(VDF‐TrFE‐CTFE), an all‐trans conformation with all F atoms located on one side of the chain is achieved, which constructs ion hopping highways and results in a high lithium‐ion transference number of 0.61. Both the Li//Li symmetric cells and the high‐voltage NCM811//Li cells show long‐term cycling stability at 25 °C.
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In this work, a rational design and construction of porous spherical NiO@NiMoO4 wrapped with PPy was reported for the application of high-performance supercapacitor (SC). The results ...show that the NiMoO4 modification changes the morphology of NiO, and the hollow internal morphology combined with porous outer shell of NiO@NiMoO4 and NiO@NiMoO4@PPy hybrids shows an increased specific surface area (SSA), and then promotes the transfer of ions and electrons. The shell of NiMoO4 and PPy with high electronic conductivity decreases the charge-transfer reaction resistance of NiO, and then improves the electrochemical kinetics of NiO. At 20Ag−1, the initial capacitances of NiO, NiMoO4, NiO@NiMoO4 and NiO@NiMoO4@PPy are 456.0, 803.2, 764.4 and 941.6Fg−1, respectively. After 10,000 cycles, the corresponding capacitances are 346.8, 510.8, 641.2 and 904.8Fg−1, respectively. Especially, the initial capacitance of NiO@NiMoO4@PPy is 850.2Fg−1, and remains 655.2Fg−1 with a high retention of 77.1% at 30Ag−1 even after 30,000 cycles. The calculation result based on density function theory shows that the much stronger Mo-O bonds are crucial for stabilizing the NiO@NiMoO4 composite, resulting in a good cycling stability of these materials.
The low Coulombic efficiency and serious security issues of lithium (Li) metal anode caused by uncontrollable Li dendrite growth have permanently prevented its practical application. A novel SiO2 ...hollow nanosphere‐based composite solid electrolyte (SiSE) for Li metal batteries is reported. This hierarchical electrolyte is fabricated via in situ polymerizing the tripropylene gycol diacrylate (TPGDA) monomer in the presence of liquid electrolyte, which is absorbed in a SiO2 hollow nanosphere layer. The polymerized TPGDA framework keeps the prepared SiSE in a quasi‐solid state without safety risks caused by electrolyte leakage, meanwhile the SiO2 layer not only acts as a mechanics‐strong separator but also provides the SiSE with high room‐temperature ionic conductivity (1.74 × 10−3 S cm−1) due to the high pore volume (1.49 cm3 g−1) and large liquid electrolyte uptake of SiO2 hollow nanospheres. When the SiSE is in situ fabricated on the cathode and applied to LiFePO4/SiSE/Li batteries, the obtained cells show a significant improvement in cycling stability, mainly attributed to the stable electrode/electrolyte interface and remarkable suppression for Li dendrite growth by the SiSE. This work can extend the application of hollow nanooxide and enable a safe, efficient operation of Li anode in next generation energy storage systems.
A SiO2 hollow nanosphere‐based composite solid electrolyte for Li metal batteries is presented. Cross‐linked TPGDA framework is in situ polymerized in liquid electrolyte, which is absorbed in a SiO2 hollow nanosphere layer to form this hierarchical electrolyte. The prepared solid electrolyte exhibits high conductivity, excellent safety, remarkable suppression for Li dendrite growth and enhanced cycle life.
Many metal–organic cages (MOCs) and a few hydrogen‐bonded organic cages (HOCs) have been investigated, but little is reported about cooperative self‐assembly of MOCs and HOCs. Herein, we describe an ...unprecedented MOC&HOC co‐crystal composed of tetrahedral Ti4L6 (L=embonate) cages and in‐situ‐generated (NH3)4(TIPA)4 (TIPA=tris(4‐(1H‐1,2,4‐triazol‐1‐yl)phenyl)amine) cages. Chiral transfer is observed from the enantiopure Ti4L6 cage to enantiopure (NH3)4(TIPA)4 cage. Two homochiral supramolecular frameworks with opposite handedness (PTC‐235(Δ) and PTC‐235(Λ)) are formed. Such MOC&HOC co‐crystal features high stability in water and other solvents, affording single‐crystal‐to‐single‐crystal transformation to trap CH3CN molecules and identify disordered NH4+ cations. A tablet pressing method is developed to test the third‐order nonlinear optical property of KBr‐based PTC‐235 thin film. Such a thin film exhibits an excellent optical limiting effect.
The supramolecular self‐assembly between metal–organic cages (MOCs) and hydrogen‐bonded organic cages (HOCs) is realized in an MOC&HOC co‐crystal composed of tetrahedral Ti4L6 cages and (NH3)4(TIPA)4 cages generated in situ. The MOC&HOC co‐crystal thin film exhibits an excellent optical limiting effect.
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