Supplementary Table S1: Normalization Data for 44 Included Studies — Electrocatalytic and Al–Water Hydrogen Production Comparative Review

Full normalization dataset for all 44 peer-reviewed studies included in the semi-systematic comparative review of electrocatalytic water electrolysis and thermochemical aluminum–water hydrogen production pathways. Contains: reference identifier, first author, year, pathway type, study scale (laboratory/pilot/system), reported values and units, conversion factors, normalized values, metric type, and methodological notes. Normalized against: kWh kg⁻¹ H₂ for electrolytic systems (PEM reference: 2 A cm⁻²; alkaline caveat noted per §2.3) and % theoretical yield (0.111 g H₂ g⁻¹ Al ≡ 100%) for Al–water systems.