CdS is a promising visible-light-driven photocatalyst, but it is highly toxic. Therefore, exploring alternatives that minimize toxicity while maintaining its photocatalytic properties is crucial. Carbon allotropes have been suggested as eco-friendly scaffolds for making high-performance photocatalysts with a small amount of toxic but visible light-responsive CdS additive to reduce environmental risk. However, it is unclear how small amounts of CdS in the nanocomposite can avoid a threat to environmental safety, and the role of surface functional groups on the physical interfaces for photocatalysis has not been sufficiently elucidated. Here, we used OH-functionalized carbon nanotubes (CNT-OH) as a support for CdS nanoparticles (NPs) and investigated the effect of CdS loading on photocatalytic activity and toxicity. Comprehensive microscopy coupled with machine learning-assisted spectroscopy revealed that electronic structure alterations occur uniquely at heterojunctions where CdS NPs contact CNT-OH, uncovering them as being catalytically active. Notably, the CNT-OH loaded by only 3 wt% CdS NPs resulted in a highly enhanced photocatalytic activity comparable to pure CdS NPs for selective oxidation of 2,5-hydroxymethylfurfural and degradation of 4-chlorophenol. These findings provide insight into heterocontact engineering using visible light-responsive catalysts and functionalized platforms to develop environmentally benign photocatalysts with high performance.

中文翻译：

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界面接触驱动的增强环境光催化对负载 CdS 的 OH 功能化碳纳米管的低生物毒性


CdS 是一种很有前途的可见光驱动光催化剂，但它具有剧毒。因此，探索在保持其光催化特性的同时将毒性降至最低的替代方案至关重要。碳同素异形体已被建议作为环保支架，用于制造高性能光催化剂，使用少量有毒但可见的光响应 CdS 添加剂来降低环境风险。然而，目前尚不清楚纳米复合材料中少量的 CdS 如何避免对环境安全的威胁，并且表面官能团在光催化物理界面上的作用尚未得到充分阐明。在这里，我们使用 OH 官能化碳纳米管 （CNT-OH） 作为 CdS 纳米颗粒 （NPs） 的支持，并研究了 CdS 负载对光催化活性和毒性的影响。综合显微镜与机器学习辅助光谱相结合，揭示了电子结构改变独特地发生在 CdS NP 与 CNT-OH 接触的异质结处，揭示了它们具有催化活性。值得注意的是，仅由 3 wt% CdS NP 负载的 CNT-OH 导致与纯 CdS NP 相当的高度增强的光催化活性，用于 2,5-羟甲基糠醛的选择性氧化和 4-氯苯酚的降解。这些发现为使用可见光响应催化剂和功能化平台开发高性能环境友好型光催化剂的异质接触工程提供了见解。