This review summarizes systematically the growth, properties, and electrochemical applications of conductive diamond.

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Transition-metal phosphides have been demonstrated as cocatalysts with great promise for photocatalytic H 2 production materials, but the insurmountable issue remains maintaining outstanding stability while achieving high photocatalytic efficiency. Herein, the rhodium phosphide (RhP x ) nanospecies as cocatalyst is firmly mounted on graphitic carbon nitride (g-C 3 N 4 ) nanosheets to realize the improved activity and stability for photocatalytic H 2 production. The maximum H 2 production rate over RhP x / g-C 3 N 4 driven by visible light diplays a 5.6-fold improvement compared with Pt/g-C 3 N 4 . Meanwhile, the apparent quantum efficiency of 18.4% is achieved at a fixed wavelength of 420 nm that far exceeds the reported g-C 3 N 4 modified with other single-transition-metal phosphides. Particularly, RhP x /g-C 3 N 4 can maintain consistently stable H 2 production when enduring over 25 cyclic reactions with a total of 100 h. The deep insight into the modification effect of RhP x nanospecies reveals that it dramatically facilitates migration and separation of photoinduced electron−hole pairs and heightens interaction at the heterointerfaces between RhP x nanospecies and g-C 3 N 4 nanosheets. This contribution extends the broad potential application of transition-metal phosphides as cocatalysts in the photocatalytic conversion from solar to hydrogen energy.

Battery-like supercapacitors feature high power and energy densities as well as long-term capacitance retention. The utilized capacitor electrodes are thus better to have large surface areas, high conductivity, high stability, and importantly be of binder free. Herein, vertically 3-/4-), respectively For assembled two-electrode symmetrical supercapacitor devices, the capacitances of EDLC and PC devices reach 30 and 48 mF cm -2 at 10 mV s -1 , respectively.They remain constant even after 10 000 cycles.

The energy densities of most supercapacitors (SCs) are low, hindering their practical applications. To construct SCs with ultrahigh energy densities, a porous titanium carbide (TiC)/boron‐doped diamond (BDD) composite electrode is synthesized on a titanium plate that is pretreated using a plasma electrolytic oxidation (PEO) technique. The porous and nanometer‐thick TiO2 layer formed during PEO process prevents the formation of brittle titanium hydride and enhances the BDD growth during chemical vapor deposition processes. Meanwhile, the in situ conversion of TiO2 into TiC is achieved. Combination of this capacitor electrode with soluble redox electrolytes leads to the fabrication of high‐performance SCs in both aqueous and organic solutions. In 0.05 m Fe(CN)63−/4− + 1 m Na2SO4 aqueous solution, the capacitance is as high as 46.3 mF cm−2 at a current density of 1 mA cm−2; this capacitance remains 92% of its initial value even after 10 000 charge/discharge cycles; the energy density is up to 47.4 Wh kg−1 at a power density of 2236 W kg−1. The performance of constructed SCs is superior to most available SCs and some electrochemical energy storage devices like batteries. Such a porous capacitor electrode is thus promising for the construction of high‐performance SCs for practical applications.

Boron doped diamond has been utilized as an electrode material to construct an electric double layer capacitor (EDLC) as well as an electrode support to form a pseudocapacitor. In a 1.0 M NaSO 4 solution, the capacitance of diamond EDLC is in the range of 3.6-7.0 µF cm -2 , comparable with those of EDLCs based on other carbon materials. During a charge/discharge process for 1000 cycles at a scan rate of 100 mV s -1 , the capacitance only decreases 5%, indicating high stability and a long life-time of such an EDLC. To improve the capacitance of diamond EDLCs, diamond was coated with a MnO 2 film to construct a pseudosupercapacitor. The MnO 2 films were electrodeposited at a constant potential of 0.9 V vs. Ag/AgCl in 0.2 M MnSO 4 solution. The mass of MnO 2 deposited per unit area, so-called the area density, calculated from the deposition charge, was controlled via the deposition time. The MnO 2 films were characterized using various techniques like SEM, XPS, and Raman spectroscopy, etc. In a 1.0 M NaSO 4 solution, the capacitance of the MnO 2 /diamond based pseudosupercapacitor rises with an increase of the mass of MnO 2 on diamond. Its maximum capacitance was found to be reached at a MnO 2 area density of 24 µg cm -2 . The capacitance obtained from voltammetry is 384 µF, or 326 F g -1 at a scan rate of 10 mV s -1 , which is comparable with the value of 406 µF, or 349 F g -1 , obtained from charge/discharge process at a current density of 3 A g -1 in the potential range 0 to 0.8 V. The capacitance was reduced by 34% after 1000 subsequent charge/discharge cycles carried out at a scan range of 100 mV s -1 .The comparison of the performance of the MnO 2 /diamond pseudosupercapacitor with that of those pseudosupercapacitors based on MnO 2 and other carbon materials indicates that diamond could be suitable for electrochemical supercapacitor applications.

The link between social class and subjective well-being (SWB) has been an important topic of inquiry, with broad implications for understanding the psychology of social class and the determinants of SWB. Prior research on this topic has focused primarily on the extent to which social class affects SWB and the factors that moderate that impact. We extend prior work by examining the concerns that account for why social class shapes SWB. In particular, we examine the role of status and power in mediating the impact of one’s social class on one’s SWB. Across five studies, we theorize and find that status mediates the impact of social class on SWB and, moreover, that status is a stronger mediator of this link than is power. Overall, these studies advance scholarly research on the psychology of social hierarchy by clarifying the interplay between social class, status, and power in relation to SWB.