Novel acid-free process intensification for the synthesis of non-precious metal-nitrogen-carbon electrocatalysts for oxygen reduction reaction

Comparative techno-economic and life-cycle analysis of precious versus non-precious metal electrocatalysts: the case of PEM fuel cell cathodes

“…S1e †). 62 Considering degradation, Stropnik et al recently developed LCA models that incorporate degradation effects, 73 and James et al recently incorporated durability adjusted operating conditions for TEA models. 74 We did not consider degradation of the PEMFC here.…”

Recent Advances in Non‐Precious Metal Single‐Atom Electrocatalysts for Oxygen Reduction Reaction in Low‐Temperature Polymer‐Electrolyte Fuel Cells

“…[67,68] Although, in a recent work the need for HF was eliminated by adding Teflon powder to the pyrolysis mixture, which leads to in situ formation of SiF 4 and template removal. [69] A further improvement in FeÀ N x site density has been demonstrated by a zinc-mediated template synthesis strategy, where Zn prevents the formation of iron carbide nanoparticles. [70] Some simple inorganic salts and oxides have also been used as templates, the advantage of these being the easier removal in water or weak acids.…”

“…Nanostructured silica has been most popular, but needs harsh conditions for removal, either HF or concentrated alkali [67,68] . Although, in a recent work the need for HF was eliminated by adding Teflon powder to the pyrolysis mixture, which leads to in situ formation of SiF 4 and template removal [69] . A further improvement in Fe−N x site density has been demonstrated by a zinc‐mediated template synthesis strategy, where Zn prevents the formation of iron carbide nanoparticles [70] .…”

Morphological and structural design through hard-templating of PGM-free electrocatalysts for AEMFC applications

“…For example, silica nanoparticles (NPs) that are generally removed through etching methods have been used to create PGM-free electrocatalysts with well-defined porosity. [35][36][37][38][39][40] So far, several different precursors have been used for making active M-N X -C electrocatalysts: porphyrins and phthalocyanines, [41][42][43][44][45] metal-organic frameworks (MOFs), particularly ZIF-8, [46][47][48] covalent frameworks, 14,49 and various combinations of nitrogen-rich organic precursors and transition metal salts. [50][51][52] The choice of precursors and the synthetic parameters has shown to affect the coordination chemistry of the metal centers 53,54 their bond lengths, 55 ligand structure, 56,57 graphitization of the carbonaceous matrix, 58 and surface defects, 59 which were manifested in the overall catalytic performance, durability, and EASD.…”

“…For example, silica nanoparticles (NPs) that are generally removed through etching methods have been used to create PGM-free electrocatalysts with well-defined porosity. 35–40…”