首页> 外文期刊>Advanced energy materials >Overcoming Charge Collection Limitation at Solid/Liquid Interface by a Controllable Crystal Deficient Overlayer
【24h】

Overcoming Charge Collection Limitation at Solid/Liquid Interface by a Controllable Crystal Deficient Overlayer

机译:通过可控的晶体缺陷覆盖层克服了固/液界面上的电荷收集限制

获取原文
获取原文并翻译 | 示例
           

摘要

Bulk and surface charge recombination of photoelectrode are two key processes that significantly hinder solar-to-fuel conversion of photoelectrochemical cell (PEC). In this study, the function of a crystal-deficient overlayer is unveiled, which outperforms a traditionally used amorphous or crystalline overlayer in PEC water splitting by exhibiting a high conductivity and large electron diffusion length to enable unlimited electron collection. The optimized approximate to 2.5 nm thickness of the crystal-deficient shell results in a depletion layer with a width of 3 nm, which overcomes the flat band limitation of the photovoltage and increases the light absorptivity in the wavelength range from 300 to 420 nm. In addition, a 50-fold increase in the conductivity yields a one-order-of-magnitude increase in the diffusion length of an electron (L-n)(approximate to 20 m), allowing for unlimited electron collection in the 1.9 m TiO2 nanowire array with the crystal-deficient shell. The controllable crystal-deficient overlayer in rutile TiO2 nanowires photoanode achieves a photocurrent density greater than 2.0 mA cm(-2) at 1.23 V versus reversible hydrogen electrode (RHE), a 1.18% applied bias photon-to-current efficiency at 0.49 V versus RHE, a faradaic efficiency greater than 93.5% at 0.6 V versus Pt under air mass 1.5G simulated solar light illumination (100 mW cm(-2)).
机译:光电极的体电荷和表面电荷重组是两个关键过程,它们严重阻碍了光电化学电池(PEC)的太阳能转化为燃料。在这项研究中,揭示了一种晶体不足的覆盖层的功能,该覆盖层通过表现出高电导率和大的电子扩散长度来实现无限的电子收集,从而优于PEC水分解中传统使用的非晶或晶体覆盖层。晶体缺陷的壳的最佳最佳厚度约为2.5 nm,从而形成了3 nm的耗尽层,从而克服了光电压的平坦带限,并提高了300至420 nm波长范围内的光吸收率。另外,电导率增加50倍,电子(Ln)的扩散长度(大约20 m)的数量级增加一个数量级,从而允许在1.9 m TiO2纳米线阵列中无限收集电子晶体不足的外壳。金红石型TiO2纳米线光阳极中可控的晶体缺陷覆盖层在可逆氢电极(RHE)下在1.23 V时实现了大于2.0 mA cm(-2)的光电流密度,在0.49 V时相对于可逆氢电极(RHE)施加了1.18%的偏置光子-电流效率RHE,在空气质量为1.5G的模拟太阳光照明(100 mW cm(-2))下,相对于Pt,在0.6 V时法拉第效率大于93.5%。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号