A sorbent for CO2 reduction from indoor air from an enclosed space. In some embodiments, the sorbent comprises a solid support and an amine-based compound being supported by the support. The sorbent captures at least a portion of the CO2 within the indoor air. The sorbent may be regenerated by streaming outdoor air through the sorbent to release at least a portion of the captured CO2. The sorbent is structured to allow indoor air to flow therein with relatively low flow resistance and relatively rapid reaction kinetics. Regeneration may be performed at relatively low outdoor air temperatures, thereby minimizing the thermal energy required for regenerating the sorbent.