Liu Bin, Qian Zheng, Shi Xiang, Su Haoqing, Zhang Wentao, Kludze Atsu, Zheng Yuze, He Chengxing, Yanagi Rito, Hu Shu
Department of Chemical and Environmental Engineering, School of Engineering and Applied Sciences, Yale University, New Haven, CT, USA.
Energy Sciences Institute, Yale West Campus, West Haven, CT, USA.
Nat Commun. 2025 Feb 12;16(1):1558. doi: 10.1038/s41467-025-56106-3.
The direct utilization of dissolved inorganic carbon in seawater for CO conversion promises chemical production on-demand and with zero carbon footprint. Photoelectrochemical (PEC) CO reduction (COR) devices promise the sustainable conversion of dissolved carbon in seawater to carbon products using sunlight as the only energy input. However, the diffusion-dominant transport mechanism and the near-zero concentration of CO(aq) (CO dissolved in aqueous solution) in static seawater has made it extremely challenging to achieve high solar-to-fuel (STF) efficiency and high carbon-product selectivity. Here, where CO(aq) as a reactant generated in situ by acidification of HCO flows continuously from BiVO photoanodes to Si photocathodes, enabling a single-step conversion of dissolved carbon into products. Our PEC device significantly increases the CO selectivity from 3% to 21%, which approaches the 30% theoretical limit according to multi-physics modeling. Meanwhile, the Si/BiVO PEC COR device achieved a STF efficiency of 0.71%. Such flow engineering achieves flow-dependent selectivity, rate, and stability in simulated seawater, thus promising practical solar fuel production at scale.
直接利用海水中溶解的无机碳进行CO转化有望实现按需化学品生产且碳足迹为零。光电化学（PEC）CO还原（COR）装置有望利用阳光作为唯一能量输入，将海水中溶解的碳可持续地转化为碳产品。然而，在静态海水中，以扩散为主导的传输机制以及CO（aq）（溶解在水溶液中的CO）的近零浓度使得实现高太阳能到燃料（STF）效率和高碳产品选择性极具挑战性。在此，通过HCO酸化原位生成的反应物CO（aq）从BiVO光阳极连续流向Si光阴极，从而实现将溶解碳一步转化为产物。我们的PEC装置将CO选择性从3%显著提高到21%，根据多物理场建模，这接近30%的理论极限。同时，Si/BiVO PEC COR装置实现了0.71%的STF效率。这种流动工程在模拟海水中实现了与流动相关的选择性、速率和稳定性，因此有望大规模实际生产太阳能燃料。
