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This work offers a successful loop-closing strategy for increasing the sustainability and lowering the manufacturing cost of epoxy materials.

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The rational design of excellent electrocatalysts is significant for triggering the slow kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in rechargeable metal–air batteries. Hereby, we report a bifunctional catalytic material with core–shell structure constructed by Co3O4 nanowire arrays as cores and ultrathin NiFe-layered double hydroxides (NiFe LDHs) as shells (Co3O4@NiFe LDHs). The introduction of Co3O4 nanowires could provide abundant active sites for NiFe LDH nanosheets. Most importantly, the deposition of NiFe LDHs on the surface of Co3O4 can modulate the surface chemical valences of Co, Ni, and Fe species via changing the electron donor and/or electron absorption effects, finally achieving the balance and optimization of ORR and OER properties. By this core–shell design, the maximum ORR current densities of Co3O4@NiFe LDHs increase to 3–7 mA cm–2, almost an order of magnitude increases compared to pure NiFe LDH (0.45 mA cm–2). Significantly, an OER overpotential as low as 226 mV (35 mA cm–2) is achieved in the designed core–shell catalyst, which is comparable to and/or even better than those of commercial Ir/C. Hence, the primary zinc–air battery employing Co3O4@NiFe LDH as an air electrode achieves a high specific capacity (667.5 mA h g–1) and first-class energy density (797.6 W h kg–1); the rechargeable battery can show superior reversibility, excellent stability, and voltage gaps of ∼0.8 V (∼60% of round-trip efficiency) in >1200 continuous cycles. Furthermore, the flexible quasi-solid-state zinc–air battery with bendable ability holds practical potential in portable and wearable electronic devices.

The application of ionic liquids in perovskite has attracted wide-spread attention for its astounding performance improvement of perovskite solar cells (PSCs). However, the detailed mechanisms behind the improvement remain mysterious. Herein, a series of imidazolium-based ionic liquids (IILs) with different cations and anions is systematically investigated to elucidate the passivation mechanism of IILs on inorganic perovskites. It is found that IILs display the following advantages: (1) They form ionic bonds with Cs+ and Pb2+ cations on the surface and at the grain boundaries of perovskite films, which could effectively heal/reduce the Cs+/I− vacancies and Pb-related defects; (2) They serve as a bridge between the perovskite and the hole-transport-layer for effective charge extraction and transfer; and (3) They increase the hydrophobicity of the perovskite surface to further improve the stability of the CsPbI2Br PSCs. The combination of the above effects results in suppressed non-radiative recombination loss in CsPbI2Br PSCs and an impressive power conversion efficiency of 17.02%. Additionally, the CsPbI2Br PSCs with IILs surface modification exhibited improved ambient and light illumination stability. Our results provide guidance for an in-depth understanding of the passivation mechanism of IILs in inorganic perovskites."Image missing"

Core/shell structured NiCo2O4@NiMn LDH hybrids were fabricated as efficient electrocatalysts for rechargeable Zn–air batteries.

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CsPbI 3 inorganic perovskites have attracted significant attention due to their desirable bandgap for tandem solar cells and excellent thermal stability. However, CsPbI 3 perovskite solar cells (PSCs) still exhibit low efficiency and high energy loss due to nonradiative recombination. Herein, functionalized Ti 3 C 2 F x quantum dots (QDs) are prepared and selected as interface passivators to enhance the performance of CsPbI 3 PSCs. The systematic experimental results reveal that Ti 3 C 2 F x QDs serve as effective passivators mainly in three aspects: 1) p-type Ti 3 C 2 F x QDs can tune the energy level of perovskite films and provide an efficient pathway for hole transfer; 2) Ti 3 C 2 F x QDs can effectively passivate defects and reduce interfacial nonradiative recombination, and 3) Ti 3 C 2 F x QDs form a barrier layer to prevent water invasion and improve the stability of CsPbI 3 PSCs. Consequently, the champion CsPbI 3 PSC with Ti 3 C 2 F x QDs treatment exhibits an excellent efficiency of 20.44% with a high open-circuit voltage of 1.22 V. Meanwhile, the corresponding device without encapsulation retained 93% of its initial efficiency after 600 h of storage in ambient air.