An updated thermionic converter was established through the introduction of a graphene anode and an optical reflector, significantly decreasing the irreversible losses inside the device and enhancing the device performances. At 1940 K, the maximum efficiency and power output density of the converter reached $76.6\%$ and $95.1\hspace{0.17em}\mathrm{W}\hspace{0.17em}\mathrm{c}{\mathrm{m}}^{-2}$. The optimum performances of the proposed model were obviously better than those achieved using a graphene-anode thermionic converter without a reflector and a traditional thermionic converter with a metal anode. Importantly, the optimal regions of the key parameters were determined for the different temperatures of the heat source and the parametric selection criteria and design strategies for the proposed model are also provided. These are extremely important as they may facilitate the implementation of the device.

中文翻译：

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石墨烯-阳极热电子转换器显示出全光子反射

通过引入石墨烯阳极和光学反射镜，建立了更新的热电子转换器，从而显着降低了器件内部的不可逆损耗并提高了器件性能。在1940 K时，转换器的最大效率和功率输出密度达到了$76.6％$ 和 $95.1\hspace{0.17em}\mathrm{w\; ^}\hspace{0.17em}\mathrm{C}{\mathrm{米}}^{-\mathrm{2个}}$。提出的模型的最佳性能明显优于使用不带反射器的石墨烯-阳极热电子转换器和带有金属阳极的传统热电子转换器的最佳性能。重要的是，针对热源的不同温度确定关键参数的最佳区域，并为所提出的模型提供参数选择标准和设计策略。这些非常重要，因为它们可以促进设备的实施。