The Li metal anode has long been considered as one of the most ideal anodes due to its high energy density. However, safety concerns, low efficiency, and huge volume change are severe hurdles to the ...practical application of Li metal anodes, especially in the case of high areal capacity. Here it is shown that that graphitized carbon fibers (GCF) electrode can serve as a multifunctional 3D current collector to enhance the Li storage capacity. The GCF electrode can store a huge amount of Li via intercalation and electrodeposition reactions. The as‐obtained anode can deliver an areal capacity as high as 8 mA h cm−2 and exhibits no obvious dendritic formation. In addition, the enlarged surface area and porous framework of the GCF electrode result in lower local current density and mitigate high volume change during cycling. Thus, the Li composite anode displays low voltage hysteresis, high plating/stripping efficiency, and long lifespan. The multifunctional 3D current collector promisingly provides a new strategy for promoting the cycling lifespan of high areal capacity Li anodes.
Graphitized carbon fiber electrode is demonstrated to improve the cycling performance of high‐areal‐capacity Li anodes due to dual reaction types, reduced current density, and confined volume change. This Li anode can deliver a high areal capacity of 8 mA h cm−2 without Li dendrites and displays low voltage hysteresis, high plating/stripping efficiency, and long cycling lifespan.
A new type of materials, organic salts in the crystal state, have ultralong organic phosphorescence (UOP) under ambient conditions. The change of cations (NH4+, Na+, or K+) in these phosphors gives ...access to tunable UOP colors ranging from sky blue to yellow green, along with ultralong emission lifetimes of over 504 ms. Single‐crystal analysis reveals that unique ionic bonding can promote an ordered arrangement of organic salts in crystal state, which then can facilitate molecular aggregation for UOP generation. Additionally, reversible ultralong phosphorescence can be realized through the alternative employment of fuming gases (ammonia and hydrogen chloride), demonstrating its potential as a candidate for visual ammonic or hydrogen chloride gas sensing. The results provide an environmental responsible and practicable synthetic approach to expanding the scope of ultralong organic phosphorescent materials as well as their applications.
Ionic crystals with ultralong organic phosphorescence (UOP) are reported. The change of cations (NH4+, Na+, or K+) in these phosphors gives access to tunable UOP colors ranging from sky blue to yellow green. Additionally, reversible ultralong phosphorescence can be realized through the alternative employment of fuming gases (ammonia and hydrogen chloride), demonstrating its potential as a candidate for visual gas sensing.
The uncontrolled growth of Li dendrites upon cycling might result in low coulombic efficiency and severe safety hazards. Herein, a lithiophilic binary lithium–aluminum alloy layer, which was ...generated through an in situ electrochemical process, was utilized to guide the uniform metallic Li nucleation and growth, free from the formation of dendrites. Moreover, the formed LiAl alloy layer can function as a Li reservoir to compensate the irreversible Li loss, enabling long‐term stability. The protected Li electrode shows superior cycling over 1700 h in a Li|Li symmetric cell.
Dendrite‐free anodes: An efficient lithium–aluminum alloy medium with increased affinity for Li and generated through an in situ electrochemical process is engineered to guide uniform Li nucleation and suppress the growth of Li dendrites.
Zinc‐ion batteries (ZIBs) have been extensively investigated and discussed as promising energy storage devices in recent years owing to their low cost, high energy density, inherent safety, and low ...environmental impact. Nevertheless, several challenges remain that need to be prioritized before realizing the widespread application of ZIBs. In particular, the development of zinc anodes has been hindered by many challenges, such as inevitable zinc dendrites, corrosion passivation, and the hydrogen evolution reaction (HER), which have severely limited the practical application of high‐performance ZIBs. This review starts with a systematic discussion of the origins of zinc dendrites, corrosion passivation, and the HER, as well as their effects on battery performance. Subsequently, we discuss solutions to the above problems to protect the zinc anode, including the improvement of zinc anode materials, modification of the anode–electrolyte interface, and optimization of the electrolyte. In particular, this review emphasizes design strategies to protect zinc anodes from an integrated perspective with broad interest rather than a view with limited focus. In the final section, comments and perspectives are provided for the future design of high‐performance zinc anodes.
A systematic and detailed summary of the research progress on zinc ion battery anodes is presented, including the causes of zinc dendrites, corrosion passivation and hydrogen evolution reaction on zinc anodes along with the existing strategies. Perspectives are provided for the future design of high‐performance zinc anodes.
It is still very urgent and challenging to simultaneously develop high‐rate and long‐cycle oxide cathodes for sodium‐ion batteries (SIBs) because of the sluggish kinetics and complex multiphase ...evolution during cycling. Here, the concept of accurately manipulating structural evolution and formulating high‐performance heterostructured biphasic layered oxide cathodes by local chemistry and orbital hybridization modulation is reported. The P2‐structure stoichiometric composition of the cathode material shows a layered P2‐ and O3‐type heterostructure that is explicitly evidenced by various macroscale and atomic‐scale techniques. Surprisingly, the heterostructured cathode displays excellent rate performance, remarkable cycling stability (capacity retention of 82.16% after 600 cycles at 2 C), and outstanding compatibility with hard carbon anode because of the integrated advantages of intergrowth structure and local environment regulation. Meanwhile, the formation process from precursors during calcination and the highly reversible dynamic structural evolution during the Na+ intercalation/deintercalation process are clearly articulated by a series of in situ characterization techniques. Also, the intrinsic structural properties and corresponding electrochemical behavior are further elucidated by the density of states and electron localization function of density functional theory calculations. Overall, this strategy, which finely tunes the local chemistry and orbitals hybridization for high‐performance SIBs, will open up a new field for other materials.
An abnormal heterostructured biphasic layered oxide cathode for sodium‐ion batteries (SIBs) is successfully constructed, and its dynamic formation process, intrinsic structural properties, and electrochemical behavior are elucidated by a series of in situ characterization techniques and density functional theory calculations. The concept of accurately manipulating structural evolution and formulating heterostructured cathode materials by local chemistry and orbital hybridization modulation is further demonstrated.
A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high‐energy‐density storage devices, but it suffers from inferior chemical compatibility with cathodes. ...Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni‐rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space‐charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high‐voltage Li‐metal batteries, innovating the design philosophy of functional CEI strategy for future high‐energy‐density batteries.
The CEI's advantage: An amorphous cathode electrolyte interphase (CEI) with superior chemical compatibility and plasticity was formed via in situ LiDFOB conversion. It endows high‐voltage hybrid solid/liquid batteries with significantly enhanced interfacial stability, durability, and dynamics.
Abstract Background The role of neoadjuvant chemotherapy (NACT) for locoregionally advanced nasopharyngeal carcinoma (NPC) is unclear. We aimed to evaluate the feasibility and efficacy of NACT ...followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in locoregionally advanced NPC. Methods Patients with stage III–IVB (excluding T3N0-1) NPC were randomly assigned to receive NACT followed by CCRT (investigational arm) or CCRT alone (control arm). Both arms were treated with 80 mg/m2 cisplatin every 3 weeks concurrently with radiotherapy. The investigational arm received cisplatin (80 mg/m2 d1) and fluorouracil (800 mg/m2 civ d1–5) every 3 weeks for two cycles before CCRT. The primary end-point was disease-free survival (DFS) and distant metastasis-free survival (DMFS). Secondary end-point was overall survival (OS). Survival curves for the time-to-event endpoints were analyzed by the Kaplan–Meier method and compared using the log-rank test. The P value was calculated using the 5-year endpoints. Results Four hundred seventy six patients were randomly assigned to the investigational (n = 238) and control arms (n = 238). The investigational arm achieved higher 3-year DFS rate (82.0%, 95% CI = 0.77–0.87) than the control arm (74.1%, 95% CI = 0.68–0.80, P = 0.028). The 3-year DMFS rate was 86.0% for the investigational arm versus 82.0% for the control arm, with marginal statistical significance (P = 0.056). However, there were no statistically significant differences in OS or locoregional relapse-free survival (LRRFS) rates between two arms (OS: 88.2% versus 88.5%, P = 0.815; LRRFS: 94.3% versus 90.8%, P = 0.430). The most common grade 3–4 toxicity during NACT was neutropenia (16.0%). During CCRT, the investigational arm experienced statistically significantly more grade 3–4 toxicities (P < 0.001). Conclusion NACT improved tumour control compared with CCRT alone in locoregionally advanced NPC, particularly at distant sites. However, there was no early gain in OS. Longer follow-up is needed to determine the eventual therapeutic efficacy.
Rechargeable lithium–metal batteries with a cell‐level specific energy of >400 Wh kg−1 are highly desired for next‐generation storage applications, yet the research has been retarded by poor ...electrolyte–electrode compatibility and rigorous safety concerns. We demonstrate that by simply formulating the composition of conventional electrolytes, a hybrid electrolyte was constructed to ensure high (electro)chemical and thermal stability with both the Li‐metal anode and the nickel‐rich layered oxide cathodes. By employing the new electrolyte, Li∥LiNi0.6Co0.2Mn0.2O2 cells show favorable cycling and rate performance, and a 10 Ah Li∥LiNi0.8Co0.1Mn0.1O2 pouch cell demonstrates a practical specific energy of >450 Wh kg−1. Our findings shed light on reasonable design principles for electrolyte and electrode/electrolyte interfaces toward practical realization of high‐energy rechargeable batteries.
Formulation of conventional electrolyte composition yields a hybrid solid/liquid electrolyte that is electrochemically compatible with the Li‐metal anode and the nickel‐rich layered oxide cathodes, which promises stable operation of a practical 10‐Ah‐grade pouch cell with a specific energy of >450 Wh kg−1.
Switching materials in channels of nonlinear optics (NLOs) are of particular interest in NLO material science. Numerous crystalline NLO switches based on structural phase transition have emerged, but ...most of them reveal a single‐step switch between two different second‐harmonic‐generation (SHG) states, and only very rare cases involve three or more SHG states. Herein, we report a new organic‐inorganic hybrid salt, (Me3NNH2)2CdI4, which is an unprecedented case of a reversible three‐step NLO switch between SHG‐silent, ‐medium, ‐low, and ‐high states, with high contrasts of 25.5/4.3/9.2 in a temperature range of 213–303 K. By using the combined techniques of variable‐temperature X‐ray single‐crystal structural analyses, dielectric constants, solid‐state 13C nuclear magnetic resonance spectroscopy, and Hirshfeld surface analyses, we disclose that this four‐state switchable SHG behavior is highly associated with the stepwise‐changed molecular dynamics of the polar organic cations. This finding demonstrates well the complexity of molecular dynamics in simple hybrid salts and their potential in designing new advanced multistep switching materials.
A new simple hybrid salt has been synthesized that exhibits reversible multistep phase transitions and an unprecedented thermally induced three‐step “silent‐medium‐low‐high” second‐harmonic‐generation switching behavior. This behavior arises from complex and stepwise molecular dynamic changes of the polar organic cations.
Public-private partnerships (PPPs) have become popular tools to deliver infrastructure and public services around the world. As an innovative public procurement approach, PPPs have drawn considerable ...attention from academic circles. In order to enhance our knowledge of PPPs, the authors conducted a systematic literature review of articles published in international journals of the Public Administration (PA) discipline. Four main topics in this discipline are identified by means of social network analysis, including PPP concept, risk sharing amongst PPP participants, the drivers of PPP adoption, and PPP performance. Seven propositions about the four topics are summarized. Directions for future research are also considered.
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