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Ultrafine in-situNiO-Ni3N heterojunction nanoparticles combine the advantages of NiO and Ni3N, and show stronger polysulfide adsorption and conversion capacity.

The inherent properties of boron nitride nanotubes (BNNTs) can be further enhanced through the control of their anisotropy. In particular, horizontally aligned BNNTs (HABNNTs) exhibit considerable potential for various applications. However, directly synthesizing HABNNTs is difficult owing to the random floating of BNNTs and the absence of directional forces. Here, we employed a simple, efficient, and universal “surface-like growth” strategy to synthesize high-density and high-quality HABNNTs in the W2B5/Zn precursor system. First, the floating range of BNNTs was restricted to the vicinity of the precursor, and then, directional forces were applied to induce BNNT directional growth along the substrate surface. Experiments and simulations confirmed that the HABNNT orientation could be controlled through manipulation of the directional forces. Furthermore, the strategy was employed for HABNNTs synthesis using the MoB2/Zn, further demonstrating the universality of the approach. Overall, this work offers a fresh perspective on the synthesis of HABNNTs, further expanding their potential applications.

Compared to other synthetic methods, the synthesis of boron nitride nanotubes (BNNTs) by the boron oxide chemical vapor deposition (BOCVD) method can balance the purity and quality of the product nanotubes. However, due to the solid reaction characteristics of boron monomers, the closed reaction system, and the synthesis temperature of over 1000 °C, growth studies of BNNTs have been in a dilemma. To this end, simultaneous thermal analysis combined with multi-atmosphere annealing experiments at corresponding temperatures is used to study the inorganic solid-state reaction of the classical BOCVD precursor B/Li2O in real time and confirmed by experimental results that lithium borate is the actual active component and catalyst. Further experiments reveal that the growth process of BNNTs and lithium borate not only consumes less of the precursor and ammonia but is also flexible in its configuration, showing exceptional efficiency and reactivity. Lastly, experiments have shown that the structure and activity of borate are equally applicable to alkali metals, alkaline earth metal, and transition metals.

Aqueous Zn-ion batteries offer the advantages of greater security and lower fabrication costs over their lithium-ion counterparts. However, their further advancement and practical application are hindered by the drastic decay in their performance due to the uncontrollable dendrite growth on Zn anodes. In this study, we fabricated a versatile three-dimensional (3D) interfacial layer (3D PVDF–Zn(TFO)2(PVDF: poly(vinylidene fluoride); TFO: trifluoromethanesulfonate), which simultaneously formed porous Zn-metal anodes (PZn) with an enhanced (002) texture, via a in situetching scheme. The 3D PVDF–Zn(TFO)2@PZn symmetrical cells leverage the advantages of surface coating and 3D porous architectures to yield extra-long cyclic lifetimes of over 5300 h (0.1 mA cm–2). The fabricated anodes were found to be compatible with MnO2cathodes, and the resulting full batteries delivered an outstanding capacity of 336 mAh g–1at 0.1 A g–1and exhibited impressive long-term reversibility with a capacity retention of 78.7% for 2000 cycles. The proposed coating strategy is viable for developing porous structures with cutting-edge designs and for textured surface engineering.

Aqueous zinc-metal batteries (Zn) have broad commercial application prospects owing to their large theoretical capacity, environmental friendliness, safety, and cost-effectiveness. However, the development of such batteries is limited by the growth of Zn anode dendrites. In this study, a highly conductive three-dimensional carbon fibers (CFs) skeleton with super-zincophilic ZnO preplaced on the surface (ZnO&CFs) was used to prepare Zn anodes. ZnO was expected to induce Zn nucleation and retard dendrite generation, and the CFs skeleton was expected to decrease the local current density to homogenize Zn ion flow and relieve the bulk stress during charging and discharging. Multifunctional regulation of the novel anode was confirmed through density functional theory calculations and experimental characterization. Symmetric cells assembled from the ZnO&CFs deposited with Zn as anodes were stable for more than 2,000 cycles at a high current density of 20 mA/cm2and exhibited a low overpotential (≈50 mV). These results indicated that the proposed three-dimensional skeleton composite anodes can effectively inhibit dendritic growth and prolong cell life, thereby facilitating the development of efficient and stable Zn anodes.