Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center, Guangzhou), Guangzhou, Guangdong 510000, China.
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong 510000, China.
J Am Chem Soc. 2023 Mar 8;145(9):4969-4974. doi: 10.1021/jacs.2c13873. Epub 2023 Feb 27.
XOR gate, an important building block in computational circuits, is often constructed by combining other basic logic gates, and the hybridity inevitably leads to its complexity. A photoelectrochemical device could realize XOR function based on the current change of the photoelectrode; however, such signal is highly sensitive to photoelectrode size and therefore requires precise manufacturing at a high cost. Herein we developed a novel XOR gate based on the light-induced open-circuit potential (OCP) of the BiO photoelectrode. Surprisingly, the OCP of BiO does not increase with light intensity according to the traditional logarithmic relationship. Instead, an unusual decrease in OCP is observed at high light intensity, which is attributed to the dramatic light-induced increase in surface states that can be easily regulated by varying the oxygen partial pressure during reactive magnetron sputtering. Based on such a nonmonotonic variation of OCP, a facile BiO-based gate is designed to realize the XOR function. Unlike the commonly used current signal, OCP is size independent, and therefore, the BiO-based gate does not require high manufacturing accuracy. Moreover, in addition to XOR, the BiO-based PEC gate also demonstrates great versatility in realizing other logic functions including AND, OR, NOT, NIH, NAND, and NOR. The strategy of modulating and applying nonmonotonic OCP signal opens a new avenue for designing size-independent reconfigurable logic gates at low manufacturing cost.
异或门是计算电路中的重要基本元件，通常通过组合其他基本逻辑门来构建，这种混合性不可避免地导致其复杂性。光电化学器件可以基于光电极电流变化来实现异或功能；然而，这种信号对光电极尺寸非常敏感，因此需要高精度制造，成本很高。在此，我们基于 BiO 光电极的开路电位 (OCP) 开发了一种新型异或门。令人惊讶的是，BiO 的 OCP 并没有按照传统的对数关系随光强度增加。相反，在高强度光下观察到 OCP 异常下降，这归因于表面态的急剧光诱导增加，这可以通过在反应磁控溅射过程中改变氧分压来轻松调节。基于 OCP 的这种非单调变化，设计了一种简单的基于 BiO 的门来实现异或功能。与常用的电流信号不同，OCP 与尺寸无关，因此，基于 BiO 的门不需要高精度制造。此外，除了异或功能外，基于 BiO 的 PEC 门还在实现其他逻辑功能（包括与、或、非、NIH、与非和或非）方面表现出极大的多功能性。调制和应用非单调 OCP 信号的策略为设计低成本、尺寸独立的可重构逻辑门开辟了新途径。
