The development of non-noble metal carbon electrocatalysts is of great significance to the development of fuel cell, metal-air battery and water-splitting technology. In this work, a highly active Co-N-doped graphene...

Oxygen reduction reaction is an important cathode reaction of fuel cell, metal-air battery, water-splitting and other devices, however, the reaction kinetics is very slow, so the development of high-performance electrocatalysts...

Two porphyrin chromophores, P1 and P2, were prepared and used as antenna units to coordinate with a metal-free organic dye, JH1, containing pyridine groups. This supramolecular self-assembly strategy can not only effectively improve the light-harvesting ability of the devices but also effectively reduces electron recombination by preventing I of the electrolyte from penetrating into the TiO surface. The DSSC based on JH1 showed a PCE of 2.46%, with a V of 615 mV, J of 6.54 mA cm, and FF of 61.18%. After supramolecular self-assembly, the J and V of the device were greatly improved. Specifically for the device based on JH1 + P2, the PCE reached 4.39%, which is about 78% greater than the PCE of the device based on JH1; this is mainly due to the J increase of 2.85 mA cm and the V increase of 93 mV. Compared to co-sensitization, supramolecular self-assembly does not require tedious optimization steps; thus, this may be a promising and convenient way to improve the overall performance of DSSCs.

For DSSCs based on stereoscopic phenothiazine dyes, JA6 with a cyanoacrylic acid anchor shows the highest PCE of 7.34%.

The development of new sensitizers and new sensitization methods is one of the important means to enhance the conversion efficiency of dye-sensitized solar cells (DSSCs); the ultimate goal is to broaden the spectral response of dyes, reduce electron recombination, and suppress dye aggregation. In this study, we have developed a series of new self-assembled dyes and applied them in DSSCs. We prepared two organic antenna chromophores S1 and S2 and coordinated them with two acceptors A1 and A2 via zinc to construct A–Zn–S series self-assembled dyes. This method is very simple and feasible and can avoid the complex synthesis steps of traditional dyes; the results show that the light-harvesting ability of devices can be improved and charge recombination can be reduced by adjusting the structures of the antenna chromophores and acceptors. The device with A2–Zn–S1 gave a power conversion efficiency of 4.25%, which was higher than those with A1–Zn–S1 (3.88%), A1–Zn–S2 (3.21%), and A2–Zn–S2 (3.52%); the main reason for this is that the different coordination combinations between the antenna chromophore and the acceptor show great differences in V oc and J sc. The device based on A2–Zn–S1 showed a high V oc of 632 mV and a high J sc of 9.54 mA cm–2; one reason for this is that S1 has better spectral responsiveness and another reason is that A2 has better steric resistance that effectively reduces charge recombination. Besides, IR spectra indicate that these self-assembled dyes anchored on a TiO2 surface by bicarboxyl anchoring groups are also very beneficial for improving the performance of dyes.