657:
before application. During the treatment, M-N4 active sites turn to aggregate spontaneously due to the high intrinsic energy, which will dramatically decrease the active site density. Therefore, increasing the active site density and creating atomic level dispersed catalyst is a key step to improve the catalyst activity. To solve this problem, we can use some porous substrates to confine the active sites or use some defect or ligands to prevent the migration of the active site. In the mean time, the porous structure or the defect will also be beneficial to the oxygen absorption process.
656:
Since the oxygen reduction reaction in fuel cells need to be catalyzed heterogeneously, conductive substrates such as carbon materials is always needed in constructing electrocatalysts. To increase the conductivity and enhance the substrate-loading interaction, thermal treatment is usually performed
615:
have been tested. as the oxygen reduction reaction catalyst and different electrocatalysis performance was achieved by these small molecules. These exciting results trigger further research of the non-noble metal contained small molecules used for the oxygen reduction reaction electrocatalyst.
672:
of the oxygen reduction reaction. To modulate the electron configuration, a simple way is to change the ligands of the metal center. For example, researchers found that whether the N atoms in M-N4 active sites are pyrrolic or pyridinic can affect the performance of the catalyst. Besides, some
32:
is reduced to water or hydrogen peroxide. In fuel cells, the reduction to water is preferred because the current is higher. The oxygen reduction reaction is well demonstrated and highly efficient in nature.
420:
1006:
Marshall-Roth, Travis; Libretto, Nicole J.; Wrobel, Alexandra T.; Anderton, Kevin J.; Pegis, Michael L.; Ricke, Nathan D.; Voorhis, Troy Van; Miller, Jeffrey T.; Surendranath, Yogesh (2020-10-19).
319:
131:
228:
491:
673:
heteroatoms such as S, P other than N can also be used to modulate the electron configuration too, since these atoms have different electronegativity and electron configuration.
664:
active site also plays an important role in the activity and stability of an oxygen reduction reaction catalyst. Because the electron configuration of M center can affects the
1071:
Zhang, Nan; Zhou, Tianpei; Chen, Minglong; Feng, Hu; Yuan, Ruilin; Zhong, Cheng’an; Yan, Wensheng; Tian, Yangchao; Wu, Xiaojun; Chu, Wangsheng; Wu, Changzheng (2020-01-21).
851:
Jahnke, Horst; Schönborn, Manfred; Zimmermann, Georg (1976). Schäfer, F. P.; Gerischer, H.; Willig, F.; Meier, H.; Jahnke, H.; Schönborn, M.; Zimmermann, G. (eds.).
1118:
Han, Yunhu; Wang, Yanggang; Xu, Ruirui; Chen, Wenxing; Zheng, Lirong; Han, Aijuan; Zhu, Youqi; Zhang, Jian; Zhang, Huabin; Luo, Jun; Chen, Chen (2018-09-12).
540:. Rather than combustion, organisms rely on elaborate sequences of electron-transfer reactions, often coupled to proton transfer. The direct reaction of O
588:
is the most common catalyst. Because platinum is expensive, it is dispersed on a carbon support. Certain facets of platinum are more active than others.
693:
Gewirth, Andrew A.; Varnell, Jason A.; Diascro, Angela M. (2018). "Nonprecious Metal
Catalysts for Oxygen Reduction in Heterogeneous Aqueous Systems".
959:"Atomic Level Dispersed Metal–Nitrogen–Carbon Catalyst toward Oxygen Reduction Reaction: Synthesis Strategies and Chemical Environmental Regulation"
773:
Ge, Xiaoming; Sumboja, Afriyanti; Wuu, Delvin; An, Tao; Li, Bing; Goh, F. W. Thomas; Hor, T. S. Andy; Zong, Yun; Liu, Zhaolin (2015-08-07).
628:
site. In biosystems, many oxygen related physical chemical reactions are carried by proteins containing the metal-prophyrin unit such as O
876:
326:
1120:"Electronic structure engineering to boost oxygen reduction activity by controlling the coordination of the central metal"
597:
732:
235:
47:
500:
138:
427:
532:
The oxygen reduction reaction is an essential reaction for aerobic organisms. Such organisms are powered by the
1168:
900:
Martinez, Ulises; Babu, Siddharth Komini; Holby, Edward F.; Chung, Hoon T.; Yin, Xi; Zelenay, Piotr (2019).
511:. While the 2e pathway reaction is often the side reaction of 4e- pathway or can be used in synthesis of H
1183:
1163:
902:"Progress in the Development of Fe-Based PGM-Free Electrocatalysts for the Oxygen Reduction Reaction"
1119:
1072:
545:
41:
The stoichiometries of the oxygen reduction reaction, which depends on the medium, are shown:
1008:"A pyridinic Fe-N 4 macrocycle models the active sites in Fe/N-doped carbon electrocatalysts"
508:
805:
1019:
970:
913:
817:
612:
549:
8:
665:
1023:
974:
917:
821:
604:
and the metal catalyst. Early catalysts for the oxygen reduction reaction were based on
1100:
1048:
1007:
957:
Yin, Hengbo; Xia, Huicong; Zhao, Shuyan; Li, Kexie; Zhang, Jianan; Mu, Shichun (2021).
852:
533:
504:
1139:
1104:
1092:
1053:
1035:
988:
939:
931:
882:
872:
833:
775:"Oxygen Reduction in Alkaline Media: From Mechanisms to Recent Advances of Catalysts"
755:
710:
669:
1073:"High-purity pyrrole-type FeN4 sites as a superior oxygen reduction electrocatalyst"
1131:
1084:
1043:
1027:
978:
921:
864:
825:
786:
747:
702:
544:
with fuel is precluded by the oxygen reduction reaction, which produces water and
1173:
751:
706:
1178:
1031:
608:
1157:
1143:
1096:
1039:
992:
935:
837:
790:
25:
1057:
943:
926:
901:
774:
759:
714:
660:
Besides active site density, the electron configuration of M center in M-N
572:
is engaged and reduced by a four-copper aggregate. Three Cu centers bind O
731:
Shao, Minhua; Chang, Qiaowan; Dodelet, Jean-Pol; Chenitz, Regis (2016).
1135:
1088:
983:
958:
886:
868:
829:
617:
496:
17:
1005:
733:"Recent Advances in Electrocatalysts for Oxygen Reduction Reaction"
585:
565:
605:
561:
600:, which represent models for the initial encounter between O
557:
850:
442:
374:
341:
287:
250:
216:
203:
153:
116:
62:
730:
620:
is also a suitable ligand for metal center to provide N
415:{\displaystyle {\ce {O2 + 2e- + H2O -> HO2- + OH-}}}
899:
651:
692:
430:
329:
238:
141:
50:
576:, and one Cu center functions as an electron donor.
495:The 4e pathway reaction is the cathode reaction in
314:{\displaystyle {\ce {O2 + 4e- + 2H2O -> 4 OH-}}}
126:{\displaystyle {\ce {O2 + 4 e- + 4H+ -> 2 H2O}}}
596:Detailed mechanistic work results from studies on
552:affects the oxygen reduction reaction by binding O
485:
414:
313:
222:
125:
1070:
223:{\displaystyle {\ce {O2 + 2e- + 2H+ -> H2O2}}}
1155:
857:Physical and Chemical Applications of Dyestuffs
853:"Organic dyestuffs as catalysts for fuel cells"
806:"Cobalt Phthalocyanine as a Fuel Cell Cathode"
772:
1117:
486:{\displaystyle {\ce {O2 + 4e- -> 2 O^2-}}}
956:
579:
1047:
982:
925:
863:. Berlin, Heidelberg: Springer: 133–181.
726:
724:
591:
468:
451:
350:
299:
276:
259:
179:
162:
105:
88:
71:
803:
1156:
810:Journal of the Electrochemical Society
721:
688:
686:
963:Energy & Environmental Materials
652:Recent development and modification
598:transition metal dioxygen complexes
501:proton-exchange membrane fuel cells
13:
1124:Energy & Environmental Science
1077:Energy & Environmental Science
683:
14:
1195:
804:Jasinski, Raymond (1965-05-01).
36:
1111:
859:. Topics in Current Chemistry.
527:
323:2e pathway in alkaline medium:
232:4e pathway in alkaline medium:
1064:
999:
950:
893:
844:
797:
766:
462:
380:
293:
190:
99:
1:
676:
522:
424:4e- pathway in solid oxide:
7:
752:10.1021/acs.chemrev.5b00462
707:10.1021/acs.chemrev.7b00335
135:2e pathway in acid medium:
44:4e pathway in acid medium:
10:
1200:
1032:10.1038/s41467-020-18969-6
22:oxygen reduction reaction
791:10.1021/acscatal.5b00524
616:Besides phthalocyanine,
24:refers to the reduction
668:, which determines the
580:Heterogeneous catalysts
927:10.1002/adma.201806545
613:coordination complexes
592:Coordination complexes
546:adenosine triphosphate
487:
416:
315:
224:
127:
1012:Nature Communications
509:solid oxide fuel cell
488:
417:
316:
225:
128:
1169:Cellular respiration
550:Cytochrome c oxidase
428:
327:
236:
139:
48:
1024:2020NatCo..11.5283M
975:2021EEMat...4....5Y
918:2019AdM....3106545M
822:1965JElS..112..526J
536:of fuel (food) by O
444:
397:
376:
343:
289:
252:
218:
205:
155:
118:
64:
1136:10.1039/C8EE01481G
1089:10.1039/C9EE03027A
984:10.1002/eem2.12085
906:Advanced Materials
869:10.1007/BFb0046059
534:heat of combustion
505:alkaline fuel cell
483:
432:
412:
383:
364:
331:
311:
277:
240:
220:
206:
193:
143:
123:
106:
52:
1184:Hydrogen peroxide
878:978-3-540-38098-6
830:10.1149/1.2423590
670:activation energy
472:
455:
435:
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379:
367:
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121:
109:
92:
75:
55:
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1164:Electrochemistry
1148:
1147:
1130:(9): 2348–2352.
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795:
794:
785:(8): 4643–4667.
770:
764:
763:
746:(6): 3594–3657.
740:Chemical Reviews
737:
728:
719:
718:
701:(5): 2313–2339.
695:Chemical Reviews
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1199:
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1154:
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1004:
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912:(31): 1806545.
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894:
879:
849:
845:
802:
798:
771:
767:
735:
729:
722:
691:
684:
679:
666:redox potential
663:
654:
647:
643:
640:reduction and H
639:
635:
631:
627:
624:part in the M-N
623:
611:. Many related
609:phthalocyanines
603:
594:
584:In fuel cells,
582:
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5:
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1149:
1110:
1083:(1): 111–118.
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499:especially in
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29:
9:
6:
4:
3:
2:
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1021:
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928:
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839:
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831:
827:
823:
819:
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811:
807:
800:
792:
788:
784:
780:
779:ACS Catalysis
776:
769:
761:
757:
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745:
741:
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619:
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457:
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406:
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388:
369:
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321:
305:
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159:
156:
148:
133:
111:
102:
94:
85:
82:
77:
68:
65:
57:
42:
37:Stoichiometry
34:
27:
26:half reaction
23:
19:
1127:
1123:
1113:
1080:
1076:
1066:
1015:
1011:
1001:
966:
962:
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905:
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813:
809:
799:
782:
778:
768:
743:
739:
698:
694:
659:
655:
595:
583:
564:complex. In
531:
528:Biocatalysts
494:
423:
322:
231:
134:
43:
40:
21:
15:
1018:(1): 5283.
969:(1): 5–18.
648:oxidation.
632:delivery, O
1158:Categories
816:(5): 526.
677:References
636:storage, O
1144:1754-5706
1105:210712326
1097:1754-5706
1040:2041-1723
993:2575-0356
936:1521-4095
838:1945-7111
618:porphyrin
523:Catalysts
497:fuel cell
478:−
463:⟶
458:−
407:−
394:−
381:⟶
357:−
306:−
294:⟶
266:−
191:⟶
169:−
100:⟶
78:−
28:whereby O
18:chemistry
1058:33077736
944:30790368
760:26886420
715:29384375
586:platinum
1049:7572418
1020:Bibcode
971:Bibcode
914:Bibcode
818:Bibcode
566:laccase
1174:Oxygen
1142:
1103:
1095:
1056:
1046:
1038:
991:
942:
934:
885:
875:
836:
758:
713:
606:cobalt
20:, the
1179:Water
1101:S2CID
736:(PDF)
556:in a
1140:ISSN
1093:ISSN
1054:PMID
1036:ISSN
989:ISSN
940:PMID
932:ISSN
887:7032
883:PMID
873:ISBN
834:ISSN
756:PMID
711:PMID
558:heme
507:and
1132:doi
1085:doi
1044:PMC
1028:doi
979:doi
922:doi
865:doi
826:doi
814:112
787:doi
748:doi
744:116
703:doi
699:118
568:, O
16:In
1160::
1138:.
1128:11
1126:.
1122:.
1099:.
1091:.
1081:13
1079:.
1075:.
1052:.
1042:.
1034:.
1026:.
1016:11
1014:.
1010:.
987:.
977:.
965:.
961:.
938:.
930:.
920:.
910:31
908:.
904:.
881:.
871:.
861:61
855:.
832:.
824:.
812:.
808:.
781:.
777:.
754:.
742:.
738:.
723:^
709:.
697:.
685:^
562:Cu
548:.
519:.
503:,
403:OH
385:HO
302:OH
1146:.
1134::
1107:.
1087::
1060:.
1030::
1022::
995:.
981::
973::
967:4
946:.
924::
916::
889:.
867::
840:.
828::
820::
793:.
789::
783:5
762:.
750::
717:.
705::
662:4
646:2
644:O
642:2
638:2
634:2
630:2
626:4
622:4
602:2
574:2
570:2
560:–
554:2
542:2
538:2
517:2
515:O
513:2
475:2
471:O
466:2
454:e
449:4
446:+
438:2
434:O
399:+
389:2
378:O
370:2
366:H
362:+
353:e
348:2
345:+
337:2
333:O
297:4
291:O
283:2
279:H
274:2
271:+
262:e
257:4
254:+
246:2
242:O
212:2
208:O
199:2
195:H
186:+
182:H
177:2
174:+
165:e
160:2
157:+
149:2
145:O
120:O
112:2
108:H
103:2
95:+
91:H
86:4
83:+
74:e
69:4
66:+
58:2
54:O
30:2
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