Xiangdong Yao's research while affiliated with Jilin University and other places

... The irreversible of C = C bond enables the framework to exhibit impressive stability under harsh conditions, and offers extended π conjugation throughout the framework for efficient electron transport, showing great potential applications in photocatalysis [20][21][22][23] . So far, the only example of 3D sp 2 carbon-linked COFs involves substituted acrylonitrile [−CH = C(CN)−] based on the Knoevenagel condensation between arylacetonitriles and aromatic aldehydes 17,24 . Nevertheless, the strong electron-withdrawing substitution of nitriles attached to the olefin bond makes the bond reversible, compromising the stability and the crystallinity of COFs 25 . ...

... 5 Regarding the energy conversion technologies, even though platinum-based electrocatalysts still offer the best performances, the scarcity and the high prices of this precious metal hinder the implementation of these compounds in commercial devices. 6,7 Different electrocatalysts have been used in the past several years, which are classified according to the pathway followed in the oxygen reduction. A two-electron reduction produces H 2 O 2 as the ORR product, while the four-electron pathway yields the direct conversion to H 2 O. 8 On one hand, the 2e − reduction produces an incomplete reduction and a lower electric current, undesirable for energy conversion but interesting for hydrogen peroxide generation. ...

... However, these approaches cannot address the abovementioned issues due to the tiny hetero atom and defect content. As a result, a novel technique for improving catalytic efficiency and stability to produce SMA is required [13,18]. Employing noble metals in the catalysis would induce a higher catalytic activity than its counterpart. ...

... 20,41,42 However, the Co-N 4 moiety is also reported as a good 4e − -ORR catalyst to water. 43,44 This controversial conclusion may be induced by the different microenvironments or surface states of the matrix that resulted in different ORR reaction paths. In particular, when oxygen-containing functional groups are introduced onto the surface of Co-N 4 -C carbon-based materials, they all suggest a significantly enhanced 2e − -ORR selectivity and ORR activity, which fully verifies the potential of Ofunctionalization in regulating the electronic properties of single-Surface Innovations Volume 10 Issue 6 ...

... This resulted in 19 mV greater half wave potential as compared to directly pyrolyzed Fe-doped ZIFs, which is a strong indication of excellent catalytic activity. 117 Li et al 118 has recently demonstrated synergistic effect of bimetals by synthesizing five iso-structural, bimetallic ZIF precursor with varying Zn/Co ratios to synthesize Co embedded, N-doped porous carbon catalysts and found that Zn 2 Co 1 -NPS@NC has shown excellent performance with half wave potential 0.894 V, greater in value than commercial Pt/C catalyst. Furthermore, experimental results indicated four electron pathways of reactions. ...

... The top-down method can be divided into physical and chemical exfoliation, corresponding to the precursors of 2D layered MOFs and 3D pillared MOFs, respectively [21]. The bottom-up method includes interfacial synthesis [71,76], surfactant-assisted synthesis [55,77], and template-assisted synthesis [78,79]. Both methods target the same goal, that is, to obtain 2D MOLs with desirable characteristics. ...

... 622 Hitherto, most of the 2D MOFs have been synthesized from the coordination of metal ions, such as Cu 2+ , Ni 2+ , or Co 2+ , with ligands derived from benzene or triphenylene with phenol (−OH), imine (−NH 2 ), or thiophenol (−SH) functional groups. For instance, Zhu et al. 623 pioneered a simple 2D oxide sacrifice approach to synthesize ultrathin FeCo MOF-74 nanosheets (named FeCo-MNS), which exhibited superior OER activity with low onset potential value of 1.528 V. Similarly, Zhang et al. 624 proposed a new class of 2D MOF containing π-conjugated [Co 3 (HHTP) 2 ] n nanosheets, which demonstrated ultrahigh mass activity (64.63 A mg −1 , 1.7 V vs. RHE) when applied in OER, proving their bright prospects in Zn−air batteries. ...

... 28-30 For example, Zhang et al. synthesized an electrocatalyst with excellent HER performance that is much higher than that of the commercial Pt/C (20 wt% Pt) by doping atomic Pt and Co atoms on the defective sites of the nitrogen modi ed graphitic spheres. 29 He et al. investigated transition metal atoms supported by graphdiyne monolayer using DFT calculations, and the catalysts show remarkable HER activity as well. 30 Recently, it was found that when adsorbents adsorb on boron nitride nanotubes (BNNT), the adsorption energy is highly relevant to the diameters of BNNT, i.e., curvature. ...

... From the view of synthetic mechanism, there are two main electrochemical methods for SACs synthesis including conventional electrodeposition [69][70][71] and potential cycling method. [72][73][74][75][76] With regards to the potential cycling method, the target metal atoms are usually as counter electrode, which can be dissolved from anode into electrolyte at high potentials and redeposited onto the substrates (working electrodes) during the cycling process. In such method, Pt foil or wire is the mostly employed counter electrode to deposit single atoms on materials. ...

... The improvement in the onset potential indicates that the presence of surface defects can modify the electronic structures and can significantly assist in promoting reaction kinetics. Such a shift in onset potential due to the presence of defects has recently been reported for hydrogen evolution reaction (HER) [41]. pH dependency is another aspect that confirms the presence of LOM participation in perovskites and other electrocatalysts [35]. ...