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A facile method to convert biomolecule‐based carbon nanodots (CNDs) into high‐surface‐area 3D‐graphene networks with excellent electrochemical properties is presented. Initially, CNDs are synthesized by microwave‐assisted thermolysis of citric acid and urea according to previously published protocols. Next, the CNDs are annealed up to 400 °C in a tube furnace in an oxygen‐free environment. Finally, films of the thermolyzed CNDs are converted into open porous 3D turbostratic graphene (3D‐ts‐graphene) networks by irradiation with an infrared laser. Based upon characterizations using scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, X‐ray diffraction, Fourier‐transform infrared spectroscopy, and Raman spectroscopy, a feasible reaction mechanism for both the thermolysis of the CNDs and the subsequent laser conversion into 3D‐ts‐graphene is presented. The 3D‐ts‐graphene networks show excellent morphological properties, such as a hierarchical porous structure and a high surface area, as well as promising electrochemical properties. For example, nearly ideal capacitive behavior with a volumetric capacitance of 27.5 mF L−1 is achieved at a current density of 560 A L−1, which corresponds to an energy density of 24.1 mWh L−1 at a power density of 711 W L−1. Remarkable is the extremely fast charge–discharge cycling rate with a time constant of 3.44 ms.

Although past research on the African American community has focused primarily on issues of discrimination, segregation, and other forms of deprivation, there has always been some recognition of class diversity within the black community. This research, on the fringe of most scholarship in the first half of the twentieth century, grew significantly with the passage of the Civil Rights Act of 1964. In this review we highlight the growth of the black middle class itself and explore the debate on the relative influence of class and race in the lives of middle-class blacks in the post–Civil Rights Era. The consensus that has emerged thus far acknowledges the increasing influence of class in the mobility chances of college-educated blacks while documenting the continued role of race in limiting black middle-class achievement. This research also finds that middle-class blacks experience discrimination both in institutional settings and in the accommodations of everyday life.

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