This special issue of the Journal of Chemical Sciences is brought out to highlight some of the important deliberations held during the 7th Interdisciplinary Symposium on Materials Chemistry (ISMC-2018), organized at the Bhabha Atomic Research Center, Mumbai on 4–8 December 2018. The articles were submitted by the invited speakers during this event, and peer-reviewed by experts in the respective field. Since the inception of the first International Symposium on Materials Chemistry in 2006, this series of biennial symposia are held every even year and are fully sponsored by the Board of Research in Nuclear Sciences (BRNS). The ISMC series was renamed in 2012 as ‘Interdisciplinary Symposium on Materials Chemistry’ from erstwhile ‘International Symposium on Materials Chemistry’ highlighting the interdisciplinary nature of the symposium.

The materials spectrum has always been in a dynamic state. The relationship between chemistry and materials science is not new. The role of chemistry in the development of new materials is growing continuously, and at the present time, the quest for new materials appears to be insatiable. The importance of this symbiotic relationship has been recognized globally in the last few decades as is manifested by the publication of several new journals in this field. The focus of the 7th ISMC was on materials for energy conversion and storage (hydrogen, solar and battery), optical materials, biomaterials, materials under extreme condition/special materials, material for the nuclear industry, etc. The ISMC-2018, like earlier meetings, turned out to be a scientifically rewarding meeting.

ISMC has always been popularising scientific contents during its meetings. Invited lectures of previous two symposia, viz., ISMC-2008 and ISMC-2014, were published in the Journal of Chemical Sciences (Vol. 122, Issue 1 (2010) (Guest Editors V. K. Jain and D. Das) and in the web version of the Journal of Materials Chemistry, RSC (UK) (Guest Editors V. K. Jain and R. K. Vatsa), respectively. With great pleasure, we bring out this issue highlighting the important contributions from ISMC-2018. In this issue, we have compiled 13 articles covering different contemporary areas of materials chemistry. This includes two articles on hydrogen energy, three on optical materials and four each on biomaterials and special materials related to the nuclear industry.

We sincerely thank the Indian Academy of Sciences and the Editor-in-Chief, Journal of Chemical Sciences, for agreeing to our proposal of bringing out this special issue, and for his continuous encouragement and support. We put on record our sincere appreciation to all the authors for their timely contributions and referees for their valuable time in the assessment of the manuscripts. We also appreciate the help from the editorial staff of the journal for the preparation of this issue.