AEM	Anion exchange membrane
AAA	Acidic-alkaline amphoteric
PA	Phosphoric acid
PBI	Polybenzimidazole
PEEK	Poly ether ether ketone
PEM	Proton Exchange Membrane
SPEEK	Sulfonated poly ether ether ketone
MEC	Microbial electrolysis cell
PEC	Photoelectrochemical
SOE	Solid oxide electrolysis
CuCl-HCl	Copper chloride-hydrochloric acid
OER	Oxygen evolution reaction
HER	Hydrogen evolution reaction
MFC	Microbial fuel cell
GHG	Greenhouse gases
PBI/ZrP	Polybenzimidazole/Zirconium phosphate
PEME	Proton exchange membrane electrolyzer
PFSA	Perfluorinated sulfonic acid
PEMFC	Proton exchange membrane fuel cell
MEA	Membrane electrode assemblies
SPES	Sulfonated polyether sulfone
YSZ	Yittria stabilized zirconia
CGO	Gadolinium doped ceria
SSZ	Scadinia stabilized zirconia
LDC	Lanthanum doped cerium
LSGM	Lanthanum gallate-based electrolyte
SPAES	Sulfonated Polyaryl Ether Sulfone