H+modulated charge-transfer in photoexcited covalent polyoxometalate-bodipy conjugates is described.The hybrid organic/inorganic molecular photoactive dyads are based on Keggin-type polyoxometalates(POMs,where KM=[PM1...H+modulated charge-transfer in photoexcited covalent polyoxometalate-bodipy conjugates is described.The hybrid organic/inorganic molecular photoactive dyads are based on Keggin-type polyoxometalates(POMs,where KM=[PM11O39]and M=Mo or W)covalently grafted via an organotin linker to a bodipy(BOD)photosensitizer.The relative potentials of the photosensitizer and POM are aligned such that lightinduced electron transfer from BOD to POM is permitted for the polyoxomolybdate KMo Sn[BOD]but not effective for the polyoxotungstate analogue K^(W) _(Sn)[BOD].In both cases,the addition of acid shifts the redox potential of the POM only,to increase the driving force for electron transfer.This leads to chargeseparation being switched on for K^(W) _(Sn)[BOD]in the presence of acid.The addition of acid to KMo Sn[BOD]accelerates charge-separation by an order of magnitude(from 2 ns to 200 ps)and is accompanied by a deceleration of charge recombination,leading to a charge-separated state lifetime of up to 1.3μs.This behaviour is consistent with proton coupled electron transfer,which has previously been observed electrochemically for POMs,but this study shows,for the first time,the impact of protonation on photoinduced electron transfer.展开更多
Boron-oxygen defects can cause serious lightinduced degradation （LID） of commercial solar cells based on the boron-doped crystalline silicon （c-Si）, which are formed under the injection of excess carriers induced ...Boron-oxygen defects can cause serious lightinduced degradation （LID） of commercial solar cells based on the boron-doped crystalline silicon （c-Si）, which are formed under the injection of excess carriers induced either by illumination or applying forward bias. In this contribution, we have demonstrated that the passivation process of boron-oxygen defects can be induced by applying forward bias for a large quantity of solar cells, which is much more economic than light illumination. We have used this strategy to trigger the passivation process of batches of aluminum back surface field （A1-BSF） solar cells and passivated emitter and rear contact （PERC） solar cells. Both kinds of the treated solar cells show high stability in efficiency and suffer from very little LID under further illumination at room temperature. This technology is of significance for the suppression of LID of c-Si solar cells for the industrial manufacture.展开更多
基金The North East Centre for Energy Materials EP/R021503/1ERC starting grant,p-TYPE 715354 and LaserLab Europe LLC002553+1 种基金G.I.,A.P.,S.B.and Y.B.M’B.thank the French National Research Agency for Grant ANR PhotoCarb(ANR-16-CE05-0025)T.P.P.C.acknowledge financial support from the Swedish Energy Agency,Crafoord Foundation and the Swedish Research Council.
文摘H+modulated charge-transfer in photoexcited covalent polyoxometalate-bodipy conjugates is described.The hybrid organic/inorganic molecular photoactive dyads are based on Keggin-type polyoxometalates(POMs,where KM=[PM11O39]and M=Mo or W)covalently grafted via an organotin linker to a bodipy(BOD)photosensitizer.The relative potentials of the photosensitizer and POM are aligned such that lightinduced electron transfer from BOD to POM is permitted for the polyoxomolybdate KMo Sn[BOD]but not effective for the polyoxotungstate analogue K^(W) _(Sn)[BOD].In both cases,the addition of acid shifts the redox potential of the POM only,to increase the driving force for electron transfer.This leads to chargeseparation being switched on for K^(W) _(Sn)[BOD]in the presence of acid.The addition of acid to KMo Sn[BOD]accelerates charge-separation by an order of magnitude(from 2 ns to 200 ps)and is accompanied by a deceleration of charge recombination,leading to a charge-separated state lifetime of up to 1.3μs.This behaviour is consistent with proton coupled electron transfer,which has previously been observed electrochemically for POMs,but this study shows,for the first time,the impact of protonation on photoinduced electron transfer.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant Nos. 51532007, 61574124 and 51472219）, the Program for Innovative Research Team in University of Ministry of Education of China （IRT13R54）, and State Key Laboratory of Optoelectronic Materials and Technologies （Sun Yat-sen University）.
文摘Boron-oxygen defects can cause serious lightinduced degradation （LID） of commercial solar cells based on the boron-doped crystalline silicon （c-Si）, which are formed under the injection of excess carriers induced either by illumination or applying forward bias. In this contribution, we have demonstrated that the passivation process of boron-oxygen defects can be induced by applying forward bias for a large quantity of solar cells, which is much more economic than light illumination. We have used this strategy to trigger the passivation process of batches of aluminum back surface field （A1-BSF） solar cells and passivated emitter and rear contact （PERC） solar cells. Both kinds of the treated solar cells show high stability in efficiency and suffer from very little LID under further illumination at room temperature. This technology is of significance for the suppression of LID of c-Si solar cells for the industrial manufacture.
