In situ synthesis of CoFe2O4 nanoparticles embedded in N-doped carbon nanotubes for efficient electrocatalytic oxygen reduction reaction

Partial deligandation activated ZIF-67 for efficient electrocatalytic oxygen reduction reaction

“…The peak in the wavelength within 1,000 cm −2 is due to the metal-bond and some functional groups, such as Co-N and methylimidazole. The peaks located within 1,100 cm −2 to 1,600 cm −2 indicate the degree of graphitization and defects in the structure (the pink block diagram in Figure 2F ) ( Zhu et al, 2020 ; Wang et al, 2022 ). From the parent ZIF-67 to the calcinated ZIF-67, it can be observed that the intensity and ratio of these peaks increase in turn, indicating that the samples gradually show graphitization and defects, which corresponds to the aforementioned thermogravimetric analysis and XPS data.…”

Transition metal oxides with perovskite and spinel structures for electrochemical energy production applications

“…Several authors proposed a solution to avoid the agglomeration of nanoparticles by coating the nanoparticles with carbon materials. This strategy prevents aggregation but, in addition, facilitates the electron transfer (Shenghai et al, 2019;Wang et al, 2022). In particular, Wang et al (2022) synthesized CoFe 2 O 4 nanoparticles embedded in N-doped carbon nanotubes and found low particle aggregation and detachment, resulting in good ORR stability.…”

“…This strategy prevents aggregation but, in addition, facilitates the electron transfer (Shenghai et al, 2019;Wang et al, 2022). In particular, Wang et al (2022) synthesized CoFe 2 O 4 nanoparticles embedded in N-doped carbon nanotubes and found low particle aggregation and detachment, resulting in good ORR stability. The protection mechanism seems to be associated with the wrapping of nanoparticles by the CNT layer.…”

Approaches to construct high-performance Mg–air batteries: from mechanism to materials design

“…140 Transition elements of Group VIIB and VIIIB elements, such as Ni, Co, Mn, and Fe, possess a variety of valences, leading to various single metal oxides. 141–143 The combination of two or more transition metals can form composite metal oxides, e.g. , the prominent spinel-type metal oxide catalysts.…”

“…140 Transition elements of Group VIIB and VIIIB elements, such as Ni, Co, Mn, and Fe, possess a variety of valences, leading to various single metal oxides. [141][142][143] The combination of two or more transition metals can form composite metal oxides, e.g., the prominent spinel-type metal oxide catalysts. The different elemental valences and material structures of the transition metals lead to different chemical and electrocatalytic properties, providing great opportunities for the development of novel and efficient cathode electrocatalysts.…”