A tightly 2D/2D heterojunction of g-C3N4(g-CN)/NiFe-layered double hydroxides (NiFe-LDH) was prepared in situ. The proper band-gap matching between NiFe-LDH and g-CN increased the transfer pathway of photogenerated electrons and holes between semiconductors. This in turn effectively reduced the recombination rate of photogenerated electrons and holes. Meanwhile, addition of g-CN to the matrix modified the surface morphology of NiFe-LDH and prevented agglomeration of two-dimensional materials while increased their ductility. Moreover, specific area of NiFe-LDH was found 3.06 times larger for 5:1-NiFe-LDH/0.8 g-CN as compared to 5:1-NiFe-LDH. The larger surface area results in availability of multiple reaction sites for the reduction of CO2. Upon exposure to light for 4 h, the product revealed 55.79 μmol/g and 20.45 μmol/g efficiency for CO and CH4 respectively, which was 3.57 times higher than pure NiFe-LDH and 4.25 times higher than pure g-CN. Furthermore, the product revealed as high as 73.2% selectivity for CO. Results authenticate the prepared g-CN containing NiFe-LDH as highly stable, efficient and selective two-dimensional materials for CO2 reduction upon exposure to light.

中文翻译：

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用于增强光催化 CO2 还原性能的原位生长 NiFe 层状双氢氧化物/g-C3N4 纳米复合材料 2D/2D 异质结

原位制备了紧密的 2D/2D 异质结 g-C3N4(g-CN)/NiFe 层状双氢氧化物 (NiFe-LDH)。NiFe-LDH 和 g-CN 之间适当的带隙匹配增加了半导体之间光生电子和空穴的转移途径。这反过来又有效地降低了光生电子和空穴的复合率。同时，在基体中加入 g-CN 改变了 NiFe-LDH 的表面形貌，防止了二维材料的团聚，同时提高了它们的延展性。此外，与 5:1-NiFe-LDH 相比，5:1-NiFe-LDH/0.8 g-CN 的 NiFe-LDH 的比表面积大 3.06 倍。更大的表面积导致多个反应位点可用于减少 CO2。光照 4 小时后，产物显示 55.79 μmol/g 和 20。CO 和 CH4 的效率分别为 45 μmol/g，比纯 NiFe-LDH 高 3.57 倍，比纯 g-CN 高 4.25 倍。此外，该产品对 CO 的选择性高达 73.2%。结果证明制备的含有 NiFe-LDH 的 g-CN 是高度稳定、高效和选择性的二维材料，可在曝光时减少 CO2。