Data-intensive exploration of the photoelectrochemical responses of main-group metal sulfides

Materials that efficiently promote the thermodynamically uphill water-splitting reaction under solar illumination are essential for generating carbon-free ("green") hydrogen. Mapping out the combinatorial space of potential photocatalysts for this reaction can be expedited using data-intensive materials exploration. The calculated band gaps and band alignments can serve as key indicators and metrics to computationally screen photoactive materials. Ternary main-group metal sulfides containing p- and s-block elements represent a promising, albeit underexplored, class of photocatalysts. Here, we computationally screen 86 candidate ternary main-group metal sulfides containing p- and s-block elements. By validating electronic structure predictions against experimental band gaps and band edges for synthetically accessible materials, we propose eight potential photocatalysts. Using computed Pourbaix diagrams, we further narrowed the candidate pool to four materials based on the predicted aqueous stability. We then synthesized and characterized these four materials and experimentally screened them for photoresponsiveness under photocatalytically relevant conditions. We also characterized their experimental band gaps and band edge positions and compared them with computational predictions. Based on the experimental screening protocols, we identify MgIn₂S₄ and BaSn₂S₅ as photoresponsive materials with sufficient aqueous stability to be considered in greater depth as potential photocatalysts for overall water-splitting. This record contains the computational predictions for the four candidates discussed in our manuscript.

能够在太阳能辐照下高效驱动热力学非自发水分解反应的材料，是制备无碳（"绿色"）氢气的不可或缺之选。借助数据密集型材料探索策略，可加速该反应潜在光催化剂组合空间的图谱绘制工作。计算得到的带隙（band gap）与能带排布（band alignment），可作为筛选光活性材料的关键指标与量化依据，用于计算筛选流程。含p区与s区元素的三元主族金属硫化物，虽是一类尚未被充分探索的材料体系，却展现出极具潜力的光催化应用前景。本研究针对86种含p区与s区元素的三元主族金属硫化物候选材料开展计算筛选。我们以可合成材料的实验带隙与能带边数据，验证电子结构预测结果，最终筛选出8种潜在光催化剂。借助计算得到的电位-pH图（Pourbaix diagram），我们基于预测的水溶液稳定性，将候选材料池进一步缩减至4种。随后我们合成并表征了这4种材料，并在光催化相关实验条件下开展光响应性能的实验筛选。我们同时测定了这些材料的实验带隙与能带边位置，并将其与计算预测结果进行对比。基于本次实验筛选流程，我们确认MgIn₂S₄与BaSn₂S₅为具备足够水溶液稳定性的光响应材料，可作为全解水光催化剂开展进一步深入研究。本数据集包含本文稿中提及的4种候选材料的计算预测结果。