Surface engineering of full-spectrum sunlight-driven CdS/NaYF4: Yb, Er for boosting photocatalytic CO2 reduction reaction

Abstract

The utilization of the Near-infrared (NIR) light accounting for about 52% in solar energy is meaningful and promising to enhance photocatalytic CO2 reduction reaction (CO2RR). In this study, an efficient ultraviolet-visible-near-infrared (UV-Vis-NIR) -activated photocatalyst for CO2RR is constructed by an in-situ surface heterojunction engineering, which is composited of nanosized CdS decorating on the up-conversion component of hexagonal NaYF4: Yb, Er (NYFYE). The as-obtained CdS/NYFYE composite photocatalyst not only shows significant CO2 reduction activities under NIR light but also exhibits a greatly boosted CO and CH4 production rate under simulated sunlight, in which the corresponding 3 h yields of CO and CH4 over CdS/NYFYE are ca. 2.7 and 4.3 times higher than that of pure CdS, respectively. Benefiting from the strong up-converted energy of NYFYE and the efficient energy transfer in the interfacial contact, the photocatalytic CO2RR can be effectively strengthened by the full spectrum of sunlight. Furthermore, the plausible photocatalytic mechanism for CO2RR over CdS/NYFYE is proposed. This work provides a feasible strategy for designing a new photocatalyst with utilization of sunlight and a durable structure to obtain high-efficiency CO2 reduction.