Energy Materials Laboratory, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ (UK).
Chemistry. 2013 Sep 27;19(40):13522-7. doi: 10.1002/chem.201300764. Epub 2013 Aug 14.
Photoelectrocatalytic conversion of CO2 to CO can be driven at a boron-doped, hydrogen terminated, p-type silicon electrode using a meso-tetraphenylporphyrin Fe(III) chloride in the presence of CF3CH2OH as a proton source and 0.1 M [NBu4][BF4]/MeCN/5% DMF (v/v) as the electrolyte. Under illumination with polychromatic light, the photoelectrocatalysis operates with a photovoltage of about 650 mV positive of that for the dark reaction. Carbon monoxide is produced with a current efficiency >90% and with a high selectivity over H2 formation. Photoelectrochemical current densities of 3 mA cm(-2) at -1.1 V versus SCE are typical, and 175 turnovers have been attained over a 6 h period. Cyclic voltammetric data are consistent with a turnover frequency of k(Si)(obs)=0.24×10(4) s(-1) for the photoelectrocatalysis at p-type Si at -1.2 V versus SCE this compares with k(Si)(obs)=1.03×10(4) s(-1) for the electrocatalysis in the dark on vitreous carbon at a potential of -1.85 V versus SCE.
在硼掺杂的、氢终止的 p 型硅电极上，使用中卟啉铁（III）氯化物，在 CF3CH2OH 作为质子源和 0.1 M [NBu4][BF4]/MeCN/5% DMF（v/v）作为电解质的存在下，可以将 CO2光电催化转化为 CO。在多色光照射下，光催化反应的光电压比暗反应的光电压正约 650 mV。一氧化碳的生成具有>90%的电流效率和对 H2 形成的高选择性。典型的光电化学电流密度为-1.1 V 相对于 SCE 时为 3 mA cm(-2)，在 6 小时内已获得 175 个循环。循环伏安数据与在 p 型 Si 上-1.2 V 相对于 SCE 的光催化反应的转换频率 k(Si)(obs)=0.24×10(4) s(-1)一致，这与在-1.85 V 相对于 SCE 的玻璃体碳上电催化反应的 k(Si)(obs)=1.03×10(4) s(-1)相比。
