Photocatalytic selective H2 release from formic acid enabled by CO2 captured carbon nitride
Photocatalytic selective H2 release from formic acid enabled by CO2 captured carbon nitride
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DOI：
10.1088/1361-6528/abed06
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发表时间：
2021-03
期刊：
影响因子：
3.5
通讯作者：
Jinghui Wang;Xia Wang;L. Qiu;Honggang Wang;Limei Duan;Zhenhui Kang;Jinghai Liu
中科院分区：
文献类型：
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作者：
Jinghui Wang;Xia Wang;L. Qiu;Honggang Wang;Limei Duan;Zhenhui Kang;Jinghai Liu
甲酸（FA）的选择性分解传统上需要在高温下使用贵金属基催化剂进行。同时，它也会遇到H2和CO2的分离，产生纯H2。温和条件下的光催化FA脱氢可以满足日益增长的可持续制氢需求。在这里，我们报道了Pt/g-C3N4在低温下光催化FA分解选择性释放H2以制备纯H2。利用低成本、易获得的尿素制备氮化碳作为无金属半导体光催化剂，并通过光沉积得到Pt/g-C3N4。电化学证据清楚地表明Pt/g-C3N4在一步分解FA中产生H2和CO2的光催化活性。在70 mW cm−2的模拟太阳光照下，阻抗最低，电子转移动力学更快。在模拟日光下，FA的产氢速率为1.59 mmol·h−1·g−1，浓度为2.65 mol l−1，是可见光下的17万倍，是紫外光下的1928倍。DFT计算进一步阐明了g-C3N4上的氮(N)活性位点对CO2分子捕获具有良好的吸附作用。然后，选择性地释放H2分子，同时分离溶液中的H2和CO2。Pt/g-C3N4上的铂（Pt）作为催化位点有助于加速H2的生成。
The selective decomposition of formic acid (FA) traditionally needs to be carried out under high temperature with the noble metal-based catalysts. Meanwhile, it also encounters a separation of H2 and CO2 for pure H2 production. The photocatalytic FA dehydrogenation under mild conditions can meet a growing demand for sustainable H2 generation. Here, we reported a photocatalytic selective H2 release from FA decomposition at low temperature for pure H2 production by Pt/g-C3N4. Low-cost and easy-to-obtained urea was utilized to produce carbon nitride as the metal-free semiconductor photocatalyst, along with a photodeposition to obtain Pt/g-C3N4. The electrochemical evidences clearly demonstrate the photocatalytic activity of Pt/g-C3N4 to produce H2 and CO2 in one-step FA decomposition. And, the impedance is the lowest under simulated solar light of 70 mW cm−2 with a faster electron transfer kinetic. Under simulated solar light, H2 production rate is up to 1.59 mmol · h−1 · g−1 for FA with concentration at 2.65 mol l−1, 1700 000 times larger than that under visible light and 1928 times under ultraviolet (UV) light. DFT calculations further elucidate that nitrogen (N) active site at the g-C3N4 has an excellent adsorption towards CO2 molecule capture. Then, H2 molecules are selectively released to simultaneously separate H2 and CO2 in solution. Platinum (Pt) at Pt/g-C3N4 as the catalytic site contributes into the acceleration of H2 production.