Efficient and directional proton transport is a very necessary energy conversion step whatever in biochemical process and artificial electrochemical energy systems. Microbial rhodopsins photosynthesis is an extremely simple but efficient natural light-driven proton pump energy conversion system. With advanced materials science and manufacturing engineering, the biohybrid nanosystems based on microbial rhodopsins and functional materials have been paid much attention.

In past five years, we devote ourselves on hybrid nanosystem through the integration of proton pump microbial rhodopsin, bacteriropoin(bR) and proteorhodopsin (pR), with functional materials for energy conversion, sensoring and artificial version studies. We focus on the artificial use of bR and pR photoelectric energy conversion through enhancing photocurrent density and enriching photocurrent waveform. Surface plasmonic effect of Au nanoparticles and proton conductor assisted 3D proton transfer have successfully improved bR and pR photocurrent, and greatly ameliorate the photoelectric performance [1, 2]. Inspired by the plasma membrane capacitor-like behavior, we developed a pR bio-capacitor system and regulated photocurrent duration time (PDT) through nanochannel resistance. Consequently, pR original transient photocurrent has been transformed into square-like waveform, which would be of broad use in further nanoenergy conversion [3, 4]. Taking advantage of pR pH-dependent photoelectric characteristics, a pR-hybrid pH sensor has achieved real-time pH detection with quick response and high sensitivity [5]. Recently, bR and pR frequency-responsive characterization was identified in the as prepared photoelectric system and further introduced to construct artificial vision [6]. Moreover, particular effort has been paid on the cooperation and adjustment between bio-components and functional materials. These original findings improve the perception on rhodopsin protein and provide mechanism insights from pure biophysical studies into the design and regulation of artificial biohybrid devices.

References:

1. Z. Guo, D. Liang, S. Rao and Y. Xiang, Nano Energy, 2015, 11, 654-661.

2. S. Rao, Z. Guo, D. Liang, D. Chen and Y. Xiang. Advanced Materials, 2015. 27(16): 2668

3. S. Rao, S. Lu, Z. Guo, Y. Li, D. Chen and Y. Xiang, Advanced Materials, 2014, 26, 5846-5850.

4. S. Rao, K. J. Si, L. W. Yap, Y. Xiang, and W. Cheng, ACS Nano, 2015, 9 (11), 11218– 11224

5. S. Rao, Z. Guo, D. Liang, D. Chen, Y. Wei and Y. Xiang, Physical Chemistry Chemical Physics, 2013, 15, 15821-15824.

6. S. Lu, Z. Guo, Y. Xiang, L. Jiang, Advanced Materials, DOI: 10.1002/adma.201603809