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The reverse water–gas shift (RWGS) reaction is a promising route for converting CO₂ into syngas, a key feedstock for fuels and chemicals in carbon-neutral energy cycles. Conventionally, RWGS operates under high-temperature and low-pressure conditions, whereas most downstream syngas-utilization processes require low-temperature and high-pressure environments. This mismatch causes substantial energy losses during process integration, underscoring the need for catalysts that perform efficiently under low-temperature and high-pressure conditions. Here, we report Na-promoted CuAl catalysts with highly dispersed Cu nanoparticles embedded in an Al₂O₃ matrix, synthesized from layered double hydroxide (LDH) precursors. The LDH-derived structure enables high Cu loadings (>49.4 wt%) without sintering, offering superior long-term stability compared to conventional impregnated Cu/Al2O3. Na promotion further enhances catalytic activity and selectivity across a wide range of temperatures, pressures, gas hourly space velocities (GHSV), and H₂/CO₂ ratios. The optimized 5NaCuAl catalyst achieved a CO formation rate of 19.32 × 10⁻⁵ molCO·g⁻¹·s₋₁ at 400 °C and 2 MPa, maintaining >99 % CO selectivity and outperforming reported Cu-based catalysts. Mechanistic studies revealed that its exceptional performance arises from (i) the formation of high-loading, well-dispersed Cu nanoparticles enabled by the LDH precursor and (ii) Na-induced electronic modulation, which enhances the redox cycle and optimizes adsorption–desorption behavior. These results provide a practical strategy for designing high-performance RWGS catalysts tailored for low-temperature and high-pressure operation, paving the way toward more efficient and economically viable carbon capture and utilization processes.