Flexible Organic Energy Devices

Organic photovoltaics (OPV) is fast emerging potential renewable, lightweight, large area and low-cost solar cell technology. Recently, the power-conversion efficiency of state-of-the-art in polymer solar cells (PSCs) has exceeded 9% and further enhancements in the efficiency towards 10% (the threshold for commercial applications) are required. Current international R&D efforts in OPV are focussed towards developing high efficiency and stable devices with both conventional and inverted solar cell configurations based on donor :acceptor bulk heterojunction concept using the soluble polymers/small molecules (electron donors) and modified fullerenes (electron acceptor) in combination with suitable interface layers. OPV group at CSIR-NPL is a very active, vibrant and internationally known centre and is carrying out R&D work on above two approaches by way of addressing the fundamental and applied facets of organic materials and devices and have already achieved efficiency in excess of 6% under CSIR TAPSUN solar energy initiative.

Dr. Suresh Chand
Chief Scientist
Head, Organic and Hybrid Solar Cell Group
Room No: 14, Main Building
CSIR-NPL, Dr. K. S. Krishnan Marg, New Delhi -110012
Email: schand@nplindia.org
Ph: +91 4560 9202/ 9353; Fax: +91 4560 9240

R&D activities

The R&D activities in our group is concentrate on device fabrication for solar cell based on polymers, hybrid polymer inorganic nano-structure, quantum dots and small molecule semiconductors: studies of hole transport layer (HTL), electron transport layer (ETL), photovoltaics, nanoscale characterization, Impedance spectroscopy and optimization of buffer layer etc. for the development of efficient stable solar cell. Other R&D activities are solution route for synthesis of various metal oxide as buffer layers, in situ synthesis of semiconductor nanoparticles in polymer matrix to modify the active layer for solar cells and nanocrystalline semiconductors by colloidal route

Recently, our group has started R&D work on design and synthesis of donor and acceptor materials for organic solar cell to improve the PCE and lifetime of the devices. Major activities in this are : a) Synthesis and characterizations of donor-acceptor polymers and small molecules; b) Synthesis of fullerene based new acceptor molecules; c) electrochemistry.

In essence the activities of OHSC group are classified in two categories as mentioned below.

1. OPV Material development

2. OPV Device Development



Dr. Suresh Chand
Physics of Energy Harvesting Division
Organic and Hybrid Solar Cell Group
Organic and Inorganic LEDs Group
CSIR-National Physical Laboratory
Dr. K. S. Krishnan Road, New Delhi 110 012, INDIA
Phone: +91 4560 9202/ 9353
Fax: +91-11-4560-9310
E-mail: schand@mail.nplindia.org


Chemical Route for Compound Semiconductor Photovoltaics

Chemical Route for Compound Semiconductor Photovoltaics is involved in synthesis and characterization materials for photovaltaics by chemical route.

Research activities


  • Development & Characterization of CIGSe & related materials prepared by non-vacuum process (colloidal route). This work on Thin film Photovoltaics is  being funded by Ministry of New and Renewable Energy (MNRE) since June 2011 and the total duration of the project is 4 years. As a Co-PI in this project our team responsible for the development of CIGS thin films. The main objective of the project is to realize the process for CIGS based solar cell (module area ~ 15x15 cm2;efficiency ~12%) by chemical route (Ink jet printing).
  • For the first time in CSIR- NPL, colloidal synthesis of CISe, CIGSe and CZTSe (replacing In in CISe with cheap and earth abundant elements) using organic capping agents TOP/TOPO has been carried out successfully. Preliminary results indicate pure-phase nanocrystals of chalcopyrites with no signatures of any peaks associated with the binary phase. Annealing studies at higher temperatures (~ 550 °C) and light-soaking experiments for longer duration is a further testimonial to their stability with superior optical and morphological properties.
  • In addition to above, to facilitate efficient charge/energy transfer across organic (polymer)-inorganic(semiconductor nanocrystal) interface for application in photovoltaics, role of different polymer matrices (MEH-PPV, P3HT) and inorganic nanocrystals (CdSe, CIGSe-related materials) has been identified. Development of CZTSSe and core-shell (CZTSe-CZTS) has been looked into.


Important facilities

S. No.

Title of the Facility

My role in brief



Photoluminescence (PL) and UV-VIS-NIR absorption spectroscopy.

Responsible for the maintenance of  these systems. Actively involved in the characterization work for various samples given through these systems.

CSIR-NPL scientists and students.


Fourier transform infrared (FTIR)Spectroscopy




Dynamic light Scattering (DLS)



Dr. Shailesh N. Sharma (Principal Scientist)
Dr. R. Jeya Kumar (Principal Scientist)


Notable Achievements (if any):

Best poster award (consolation Prize) for the poster entitled “Transition from CZTSe to CZTS via Multicomponent CZTSSe: Potential Low Cost Photovoltaic Absorbers” by Parul Chawla, Shailesh N. Sharma, Parth Vashishtha and Suresh Chand presented at TAPSUN Conference held at NPL during 4-5th Dec. 2012.

Section # Flexible Organic Energy Devices

Section Leader
Dr. Shailesh Narayan Sharma
Principal Scientist