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New arylamine-based sensitizers for p-type dye-sensitized solar cells (DSSCs) have been synthesized and used for p-type DSSCs. The best conversion efficiency reaches ∼0.1%. Sensitizers with two anchoring carboxylic acids lead to higher open-circuit voltages, short-circuit currents, and energy conversion efficiencies.

In this report, a pivotal improvement in the performance of dye‐sensitized solar cells has been achieved, thus taking it one step closer toward the commercialization. Through the stepwise modification on the anthracene‐based organic sensitizers, the alteration of alkyl to alkoxy chain and incorporation of electron deficient moieties in the new sensitizing dyes TY3, TY4, and TY6 are found to play a significant role in the efficiency enhancement. The dye TY6, when tested under 1 sun (AM 1.5G) illumination, is found to exhibit the best efficiency of 8.08% in the series reported here. Taking it further, sensitizer TY6 achieves a milestone by displaying an efficiency of 28.56% when tested under T5 fluorescent illumination of 6000 lux and 20.72% under same illuminance from a commercial light emitting diode light source. Such an excellent performance can be attributed to its outstanding J SC and V OC, which are characteristic properties of these anthracene dyes.

Electrodes with the functionality of amino acids can be easily prepared by taking advantage of strong sulfur−gold interactions and immersing gold electrodes into cysteine solutions. Such electrodes exhibit excellent sensitivity and selectivity toward copper(II) determination, because the bidentate chelation of amino acids toward copper(II) is effective and far superior than that toward any other metal ions. In this study, we demonstrate that at a preconcentration time of 5 min the cysteine-modified electrode has a dynamic range of 2 orders of magnitude (from 5.0 to 0.050 μg/L) and the detection limit is as low as 25 ng/L (0.39 nM). This method is applied to the determination of copper(II) in two reference materials, SLEW-2 (river water, 1.62 μg/L) and CASS-3 (seawater, 0.517 μg/L). The results agree satisfactorily with the certified values.

New zinc porphyrins Y2 and Y2A2 have been utilized in perovskite solar cells specifically as hole-transporting materials (HTMs) rather than photosensitizers. The combination of MAPbI3 as photosensitizer and porphyrins as HTMs is a potential alternative to well-known MAPbI3/Spiro-OMeTAD hybrids owing to high performance and versatility toward molecular engineering of porphyrin families. A high efficiency of 16.60% is achieved by n-butyl tethered Y2 HTM (V OC = 0.99 V; J SC = 22.82 mA cm–2) which is comparable to that of Spiro-OMeTAD of 18.03% (V OC = 1.06 V; J SC = 22.79 mA cm–2). Both materials possess similar highest occupied molecular orbital level and the same order of magnitude of hole mobility at 10–4 cm2 V–1 s–1. The slightly poorer performance of 10.55% (V OC = 1.01 V; J SC = 17.80 mA cm–2) is obtained for n-dodecyl tethered Y2A2 HTM. This is believed to stem from more surface pinholes when deposited on perovskite leading to an order of magnitude slower mobility.

New metal-free dyes with a furan moiety in the conjugated spacer between the arylamine donor and the 2-cyanoacrylic acid acceptor have been synthesized, and high efficiency dye-sensitized solar cells were fabricated using these molecules as light-harvesting sensitizers.

We have devised new porphyrin dye Y1A1 for photovoltaic application under both light sources of AM1.5G standard condition and low light intensity at 300 ~ 2400 lux. The dye Y1A1 tailored with two 3,5-di-tert-butyl-4-methoxyphenyl groups at meso-10,20-positions which helps the solubility of the molecule in solvents and avoids involvement of the hazardous chemical n-butyllithium during the synthesis of some typical high efficiency porphyrins such as YD2-o-C8 and LD-series dyes. The dye is also structurally simple so that large-scale synthesis for future industrial application becomes feasible. The Y1A1-based cells were found to exhibit higher performance using I -/I 3 rather than Co 2+/3+ electrolyte in the presence of CDCA co-adsorbent. Addition of Li + together with removal of GuSCN as electrolyte additives benefit the performance in terms of higher capacitance at compensate of surface charge recombination and electron lifetime. The optimized cells based on Y1A1 showed a power conversion efficiency of 9.22% at AM1.5G condition and as high as 19.5%illuminated under 350 lux of LED light. IntroductionSolar cells are well-known technologies in terms of converting energy from sun to a flow of electrons. To provide a controllable and comparable testing condition for solar cells, standard 1 Sun condition (100 mW cm -2 ) is generally equipped in the laboratory for mimicking the outdoor environments which typically shed lights with intensity of >100,000 lux. In contrast, indoor lights surrounding the living places of the community can be considered as low light or dim light due to relatively lower photon flux. These places including homes, schools, offices, factories, hospitals and stores require brightness of light sources typically ranging between 300~500 lux. Higher light level demand for specific area such as laboratories, reading rooms, production halls, first aids and show rooms require the illuminated light of 500~1500 lux. With the thriving concept of indoor energy-harvesting aiming at these reachable light sources, dye-sensitized solar cells (DSCs) are certainly one of the most promising light-to-electricity conversion technologies. 1 DSCs have drawn growing attention since the pioneer work initiated by Grätzel's groups. 2 In the past two decades, molecular engineering of dyes yields several kinds of molecular architectures for efficient solar-to-electricity conversion. 3, 4 These high performance dyes includes the ruthenium polypyridyl complexes, 5, 6 the arylamine-based organic dyes 7-12 and the porphyrin-based dyes. 13-15 Graphical AbstractA new porphyrin dye Y1A1 has been devised for high performance dye-sensitized solar cells under the irradiance of either AM1.5G simulated sunlight or fluorescent/LED based dim light.

Series of dyes containing a cyanovinyl entity in the spacer have been developed and characterized. Dye-sensitized solar cells (DSSCs) using the dyes as the sensitizers exhibited good efficiencies ranging from 3.48−4.92%, which reached 45−70% with respect to that of an N719-based device fabricated under similar conditions. In general, better DSSC performances are observed with molecules having a shorter distance between the internal cyanovinyl entity and the amine donor. Computational analysis indicated that the cyanovinyl entity may behave as a charge trap, especially in the long molecules studied, where the cyanovinyl group is away from the electron-donating amine by two or more aromatic groups. A positive correlation is observed between the theoretically calculated product of oscillator strengths and the charge shift at the cyanoacrylic acid group and the measured short-circuit current in DSSCs. Therefore, it is likely that the charge-trapping in the cyanovinyl entity reduces the electronic interaction between the dye and the attached TiO2 and, therefore, compromises the DSSC performance.