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·1540·                            精细化工   FINE CHEMICALS                                  第 35 卷

            催化剂进行 ICP-AES 分析可知,VO@g-C 3 N 4 -T 催               催化活性。剥离成薄片的 g-C 3 N 4 和乙酰丙酮氧钒络
            化剂中 V 质量分数仍能达到 9.69%,和新鲜的 9.78%                    合可能形成一种特殊的结构,且具有较强的协同效
            相比,说明催化剂中钒元素在反应中基本没有溶脱,                            应,导致这种催化剂具有合适的带差,对可见光催
            这与文献报道基本一致          [11] 。在对反应液进行 ICP-AES          化苯羟基化具有较好的响应。富含氮原子的纳米薄
            测试发现,反应液中没有发现钒元素的存在,可能                             片石墨化氮化碳表面对于吸收可见光、扩散反应介
            是钒化合物和 g-C 3 N 4 具有非常强的结合力所致。结                     质也具有重要的作用,促进了苯羟基化中 C—H 的
            合套用 5 次后的 SEM(图 4F)表征可知,该催化剂                       活化。
            套用前、后其形貌没有明显改变,这可能是该催化
                                                               参考文献:
            剂稳定性较好的重要原因。
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