Two papers on decent journals claim that high efficiency compact layer free perovskite solar cells are demonstrated, while another paper by Henry Snaith gives hints of non-operation of solar cells with such structures.

The first one is on J. Am. Soc. Chem.

A 13.5% PCE is claimed with no testing condition (scan direction, scan rate, delay time, pre-testing condition, etc) mentioned.

http://pubs.acs.org/doi/full/10.1021/ja508758k

The second one is the just online Nat. Comm paper.

http://www.nature.com/ncomms/2015/150323/ncomms7700/full/ncomms7700.html

The J-V hysteresis is given in supporting information. The results look promising. Both reverse and normal scan can give out a PCE of >10%. But a stablizing current output at maximium power point is not given.

Another paper from Henry Snaith show even more interesting results.

http://pubs.rsc.org/en/content/articlelanding/2015/mh/c4mh00238e#!divAbstract  

They show even they reads high PCEs from J-V scans, but the stablizing current output is zero.

Interesting.

P.S. Professor Kamat's JPCL viewpoint as below on perovskite solar cells measurement

http://pubs.acs.org/doi/full/10.1021/acs.jpclett.5b00289

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Table 1.Guidelines for Proper Characterization of Perovskite Solar Cells

(1) mask cell appropriately and measure area

(2) calibrate illumination source

(3) determine steady-state JSC and VOC and monitor stability

(4) record forward and reverse J–V curves at various scan rates

(5) measure steady-state photocurrent at several voltages near Pmax

(6) calculate JSC,INT by integrating IPCE data

(7) cross check results from steps 3–6 for self-consistency

(8) perform statistical analysis across multiple sample sets

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